SQL. You possibly can construct fashions in your sleep. You’ve run dozens of A/B assessments. So why aren’t you getting promoted?
The reality is, most knowledge scientists plateau not as a result of they lack technical abilities, however as a result of they don’t perceive what truly modifications between ranges. Firms hand you a ladder with obscure rungs labeled “influence,” “scope,” and “strategic pondering” after which anticipate you to determine what these phrases imply in observe.
Many sensible and expert knowledge scientists get caught at L4 for years, grinding on more durable technical issues, whereas their friends leap to L5 by shifting how they consider their work. The profession ladder in knowledge science isn’t a straight line of accumulating extra instruments and strategies. It’s a sequence of elementary shifts in the way you outline issues, create worth, and affect choices. Every promotion requires you to play a special sport and it isn’t at all times clear precisely when the foundations have modified.
On this publish, I’ll break down what modifications at L3, L4, L5, and L6; not when it comes to summary competencies, however in concrete behaviors and mindset shifts. These are the patterns I’ve noticed throughout dozens of promotions (and seemingly high-performing however stagnant careers) at main tech firms. Let’s decode the hidden ladder collectively.
L3 → L4: Changing into Dependable
The soar from L3 to L4 is deceptively easy to explain however surprisingly exhausting to execute: you need to shift from being an executor to being an proprietor.
At L3, you’re given well-defined duties. A PM or senior knowledge scientist scopes the work, breaks it into steps, and checks in continuously. You write the SQL question. You construct the dashboard. You run the experiment. Another person worries about whether or not you’re fixing the suitable drawback, whether or not the metric is smart, or what occurs after you ship.
At L4, you personal the end result. The distinction exhibits up in dozens of small behaviors that compound into a totally totally different working fashion.
Ending cleanly turns into non-negotiable. L3s can get away with “I constructed the mannequin, right here’s the pocket book.” L4s ship: documentation that others can use, code that passes evaluate on the primary strive, outcomes offered in a means that results in clear choices. If you hand off work, nothing comes again to you with “wait, what does this column imply?” or “are you able to rerun this with the corrected knowledge?”
Constructing belief means your supervisor stops checking your work. They know that once you say the evaluation is finished, it’s truly achieved: edge circumstances dealt with, knowledge high quality verified, outcomes sanity-checked towards instinct. Early-career knowledge scientists usually underestimate how a lot of L4 is just proving you received’t create surprises. Reliability isn’t glamorous, however it’s the inspiration of every part that comes after.
Asking higher questions separates L4s from folks caught at L3. When a PM asks for “conversion price by phase,” an L3 builds the question and returns the numbers. An L4 asks: “Are we making an attempt to establish which phase to focus on, or validate an current speculation? As a result of that modifications whether or not we must always have a look at conversion price or incremental carry.” You begin seeing the why behind requests, which implies you possibly can usually resolve the precise drawback slightly than simply the said query.
Seeing the subsequent step earlier than being advised is likely to be a very powerful L4 conduct. You end analyzing experiment outcomes, and as an alternative of ready for somebody to ask, you’ve already drafted three follow-up experiment concepts with tough scopes. You see a knowledge high quality difficulty and file the ticket to repair it earlier than anybody notices the bug of their dashboard. You ship the quarterly metric evaluate and proactively flag the one metric that’s trending in a regarding course.
Right here’s what this appears to be like like in observe: You ship your first challenge end-to-end with out PM handholding. Possibly it’s redesigning the person onboarding circulate. You don’t simply run the experiment, you write the one-pager proposing it, outline the metrics with the PM, implement the logging with the engineers, analyze the outcomes, current to management, and coordinate the total rollout. Six months earlier, 5 totally different folks would have pushed these steps. Now it’s you. That’s the L4 transition.
The L3 → L4 soar is about proving you may be trusted with larger issues. As soon as your supervisor is aware of you’ll end what you begin, see round corners, and ship high quality work with out supervision, they can provide you ambiguous initiatives. Which brings us to L5.
L4 → L5: Changing into Strategic
If L3 → L4 is about dependable execution, L4 → L5 is about changing into the one that defines what issues are value fixing within the first place.
That is the place most knowledge scientists get caught. They preserve perfecting their execution—working cleaner experiments, constructing extra refined fashions, mastering new instruments—whereas lacking the elemental shift their firm expects. L5 isn’t about doing the work higher. It’s about deciding what work ought to exist.
Scoping ambiguous issues turns into your core ability. At L4, a PM fingers you a query: “Why did engagement drop final month?” You examine and return a solution. At L5, management says “development is slowing” and also you flip that into 5 concrete hypotheses, a prioritized investigation plan, and a timeline for decision-making. You’re comfy with ambiguity as a result of your job is to resolve it for others.
This exhibits up in the way you strategy new initiatives. A product crew says “we have to enhance retention.” An L4 asks: “What evaluation would you like?” An L5 pushes again with construction: “Let’s outline what retention success appears to be like like first. Are we optimizing day-7, day-30, or long-term engagement? What’s the enterprise case? Are we making an attempt to hit an org-level KPI or validate a product guess? That modifications every part about how we must always strategy this.” At L5, you’re doing the strategic pondering that no person else has time for.
Designing metrics separates L5s from L4s greater than every other ability. At L4, you measure what you’re advised to measure. At L5, you perceive that metric alternative is technique. When your organization debates whether or not to optimize for each day lively customers or time spent per session, you’re the one that can articulate the tradeoffs: DAU optimization would possibly juice short-term engagement by means of notifications whereas degrading long-term person expertise; time-per-session may reward addictive options over beneficial ones. L5s don’t simply calculate metrics, as an alternative they take into account whether or not they’ll drive the suitable conduct. It’s understanding that you would be able to optimize the unsuitable metric completely and nonetheless hurt the enterprise.
Influencing PMs turns into a core a part of your job. At L4, you’re responsive: PMs set priorities and also you execute. At L5, you’re proactive: you notice alternatives within the knowledge and persuade PMs to guess on them. This is likely to be analyzing person conduct knowledge, noticing {that a} small phase has 10x increased lifetime worth, constructing a enterprise case for why the product crew ought to focus their subsequent quarter on increasing that phase, and driving the dialog in planning conferences till it’s on the roadmap.
This affect requires a totally totally different communication fashion. You cease answering questions and begin shaping which questions matter. You write technique memos, not evaluation studies. You current suggestions, not findings. The evaluation remains to be rigorous, however it’s in service of driving choices, not documenting what you probably did.
Pondering in tradeoffs is likely to be the deepest L5 mindset shift. L4s search the “proper reply.” L5s perceive that almost all product choices contain competing values with no clear winner. And your job is to make these tradeoffs specific so leaders can resolve. Ought to we launch the function with recognized bugs to hit a deadline, or delay for high quality? There’s no purely data-driven reply, however you possibly can quantify the tradeoffs: “Launching now reaches 2M customers throughout peak season however traditionally our buggy launches see 40% increased assist prices and 15% increased churn. Right here’s what that appears like in greenback phrases.”
Right here’s what L5 appears to be like like in observe: You lead a brand new experiment technique that modifications the product roadmap. Possibly development has stalled and the crew is working disconnected assessments. You plan a scientific testing framework: outline a coherent person journey to optimize, map out the highest-leverage factors to check, create a shared metric tree so groups aren’t optimizing conflicting objectives, and set up a six-month roadmap of experiments sequenced by dependency and studying worth. This isn’t evaluation, it’s technique. You’ve formed how your complete product org thinks about development for the subsequent two quarters. That’s the L5 transition.
The L4 → L5 soar is about increasing from executing options to defining issues. When you’ve confirmed you possibly can take ambiguous conditions and switch them into clear paths ahead, you’re able to scale your influence past your individual work.
L5 → L6: Changing into a Multiplier
The L5 → L6 transition is the toughest to make, and the simplest to misconceive. It’s not about being a extra strategic particular person contributor. It’s about changing into a power multiplier: somebody whose influence scales by means of others. This may be as each an IC or as a supervisor.
At L6, your worth isn’t measured by the standard of your individual analyses. It’s measured by how a lot better you make everybody else’s work. This can be a brutal psychological shift for high-performing particular person contributors who constructed their careers on private excellence.
Setting frameworks others use turns into your major output. An L5 would possibly run one of the best experiment in firm historical past. An L6 creates the experimentation framework that makes each crew’s experiments higher. This may very well be a call tree for statistical check choice, a template for experiment one-pagers that forces groups to suppose by means of success metrics upfront, or a standardized strategy to measuring incremental carry that turns into the corporate default.
Typically an L6’s output seems to be nothing groundbreaking individually however optimizes work throughout the org. For instance, a reasonably fundamental “metrics evaluate guidelines” that stops dozens of groups from making metric-selection errors that will waste quarters of labor.
Mentoring issues greater than you’d anticipate. At L6, you’re accountable for creating L4s and L5s throughout the group, not simply your speedy crew. This goes past code evaluations. You’re educating folks easy methods to suppose strategically. When an L4 brings you a thorny evaluation drawback, you don’t resolve it for them—you ask the questions that assist them resolve it themselves: “What determination does this evaluation must assist? Who’s the viewers and what do they already consider? What would make you assured sufficient within the consequence to guess your credibility on it?”
The multiplier impact exhibits up right here: one hour of your time educating an L4 easy methods to scope issues correctly would possibly save them dozens of hours over the subsequent 12 months, and enhance each challenge they contact. Your impact-per-hour by means of mentoring usually exceeds your influence from doing the work your self.
Driving alignment throughout groups turns into vital at L6 since you’re engaged on issues too huge for any single crew to personal. Possibly knowledge high quality points are hurting three totally different product areas, however no person owns the underlying instrumentation. An L5 would possibly doc the issue and escalate. An L6 convenes the stakeholders, builds consensus on severity, proposes an answer that works throughout all groups’ constraints, and drives it to completion regardless of crossing organizational boundaries.
This requires a totally totally different influencing toolkit than L5. You’re not convincing one PM to prioritize your challenge, you’re aligning a number of groups round a shared drawback when every crew has competing priorities. You get comfy with statements like: “I do know this creates additional work to your crew this quarter, however right here’s why it unblocks three different groups and saves us all six months of ache later.” You make invisible issues seen, and also you make coordination issues tractable.
Recognizing systemic knowledge points earlier than they change into crises is basic L6 work. You discover that experiment outcomes have been inconsistent recently, dig in, and uncover {that a} latest instrumentation change broke randomization for five% of customers in a delicate means that no person caught. An L5 would file a bug. An L6 sees the sample: that is the third instrumentation difficulty this 12 months, which implies the issue isn’t particular person bugs, it’s that we lack a testing and evaluate course of for instrumentation modifications. You plan the method, get buy-in from engineering management, and implement it. Six months later, instrumentation high quality has improved throughout the corporate, and most of the people by no means know you’re the rationale why.
Right here’s what L6 appears to be like like in observe: You create an experimentation evaluate course of that improves high quality org-wide. It’s not simply higher documentation, it’s the implementation of a light-weight peer evaluate system the place any experiment over a sure measurement will get reviewed by a knowledge scientist from one other crew earlier than launch. You write the rubric, prepare the reviewers, run the primary 20 evaluations your self to calibrate requirements, and set up a suggestions loop to enhance the method. Inside two quarters, experiment high quality has measurably improved (fewer invalid assessments, higher metric choice, clearer documentation), and groups throughout the corporate are making higher product choices as a result of their experiments are extra reliable. You personally reviewed 5% of the experiments, however your framework improved 100% of them. That’s the L6 transition.
The L5 → L6 soar is about scaling your self by means of methods, folks, and processes. Your work turns into extra summary: you’re optimizing how the group works, not fixing particular person issues. It might really feel much less satisfying in some methods (no person celebrates an excellent framework launch), however the leverage is extraordinary.
The Sample Throughout Ranges
Trying throughout these transitions, a transparent sample emerges: development isn’t about studying extra strategies; it’s about increasing the way you see and form the work.
L3 → L4: You develop from job completion to drawback possession. The query modifications from “Did I do what I used to be requested?” to “Did I resolve the issue fully?”
L4 → L5: You develop from drawback fixing to drawback definition. The query modifications from “How do I resolve this?” to “What drawback ought to we be fixing?”
L5 → L6: You develop from defining issues to constructing the methods that assist others outline and resolve issues. The query modifications from “What ought to our crew work on?” to “How can we make the whole group more practical?”
Every stage requires you to zoom out. Every stage requires you to let go of the satisfaction of hands-on work and embrace extra summary, extra leveraged contributions. Every stage requires totally different abilities—however extra importantly, alternative ways of serious about what your job truly is.
The toughest half? No one tells you this explicitly. It’s a must to decode it from obscure suggestions about “influence” and “strategic pondering” and “scope.” Firms anticipate you to determine that promotion isn’t about getting higher at your present stage’s sport, it’s about noticing the brand new sport and beginning to play it earlier than anybody asks you to.
So right here’s my problem to you: Mirror on which mindset you’re at present embodying, and which one you need to develop into.
Are you executing reliably however nonetheless ready for others to scope your work? You’re prepared to start out performing like an L5: suggest the issue definition as an alternative of ready for it. Are you already scoping issues however solely to your personal initiatives? You’re prepared to start out performing like an L6: search for the frameworks and methods that will make everybody’s work higher.
Don’t await a promotion to alter how you’re employed. Begin taking part in the subsequent stage’s sport now. Your promotion is the corporate recognizing that you just’ve already made the shift—not allowing you to start out.
The concepts on this publish come from my new e book, The Strategic Data Scientist: Level Up and Thrive in the Age of AI (Amazon affiliate hyperlink).
The e book offers actionable frameworks, detailed plans, and real-world examples for making use of these concepts instantly in your day-to-day work—together with particular workout routines for making every stage transition, templates for the paperwork you need to be writing at every stage, and methods for working with AI instruments whereas constructing the strategic abilities that preserve you forward of automation.
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