Some big tech organizations basically do this without the pay. Essentially in some FAANG corps, you have to prove having worked at L+1 while still at L to get promoted to L+1.

In my biased / personal experience, the veracity of such a bar kinda deteriorates over time and the short average tenure makes most promo processes corrupt B.S. when folks are more incentivized to just quit and join somewhere else for more money.

Also, this process and your suggestion at a "probation" tends to motivate working harder for the window being measured, regardless of how actually adept or well equipped the person is at the level for which they're trying to illustrate competence.

> You have to prove having worked at L+1 while still at L to get promoted to L+1.

Yes, and this line of thinking has spread to many orgs. And as you point out people tend to just move elsewhere instead.

The length of the observation window is one thing, and more fundamentally employees are asked to work above their pay grade in hope for it to be noticed/recognized, which is never a fun thing to do.

Then comes the responsibility problem: If a dev want to become a manager, there's no way to let them deal with HR, write performance reviews and do 1 on 1s including private information as a trial. They need the actual role inked in their contract, have people treat them as a manager. They can't be doing it as a role playing exercice. A probation period could work, but I think it would be pretty awkward to have them step down after 3 months.

The problem is the step function differences. Someone may be an exceptional individual contributor but a lousy manager even at a relatively low level. A manager of a small team may not be great at handling a big team that may need to be realigned.

Some of it's about a company having reasonable tracks for people depending upon their preferences. But people may also have preferences they're just not suited for.

Most places I've worked require you to be operating at the level you're going to be promoted to before you get actually promoted.

But you can't e.g. prove your ability to manage without being given a team to manage...

Even better, have time-limited temporary promotions, which automatically revert after 6 months or a year. Permanent promotions are generally only available to those who have done a temporary promotion in the past.

That gives the organisation a way to tell if you are ready for permanent promotion, but removes the humiliating experience of "not passing your probation".

This doesn't seem to work so great in practice. Same story for demotions and pay reductions. Not that they can't happen. It's just not the norm for understandable reasons.