Unsurprisingly, I go through interviews from time to time with startups, or talk with recruiters and founders. And for a while now, one signal has tended to come back. Generally, I try to pay attention to patterns and signals; in particular, I try to see beyond the way they first appear to me.

In this case, the signal is: that I might not have enough experience.

Disappointing, isn’t it? But behind what might look like a blow to the ego, I saw an opportunity to reflect on what we call experience in my professional field, and in technical professions more generally.

The short version of that reflection is that seniority and experience, understood as technical legitimacy, are roughly orthogonal. You can have one without the other, and vice versa.

To illustrate: a 23-year-old intern isn’t expected to have high-level technical expertise. The only truly legitimate expectation is that they be curious and motivated. Conversely, a 40-year-old engineer generates much higher expectations in terms of technical expertise. That’s reasonable, since they presumably have more “experience”.

But there’s actually a bias in that framing. Indeed, we assume that this engineer has genuinely accumulated experience, and not just seniority. The bias is to confuse seniority with experience. And that’s where I see a career risk: letting your seniority decorrelate from your experience.

I believe this distinction is one reason some people move toward management roles. As a way to no longer have to justify technical experience against seniority. The motivation is to preserve a form of credibility with the organization and one’s peers.

Seniority is systematic, and easily measured. And for that reason, some are tempted to use it as a proxy for experience. Experience, on the other hand, is empirical. It’s a set of knowledge, practices, situations encountered, problems solved, and initiatives taken. It can’t be measured simply. Above all, it’s a very individual measure.

The truth is that you can’t be consistent and credible if seniority and experience are “too” decorrelated. That’s a subjective measure, I know. But it’s the measure that each of the recruiters I talked to was trying to evaluate. That’s why staying in a situation where you no longer learn amounts to letting seniority accumulate without experience: pure sabotage.

Beyond this signal, I realize the importance of refocusing on my learning, on the experience I have to tell, and on how to structure it. This blog, more broadly, is my response to that signal.