[GoatOfAplomb]

Some years ago, the official ladder descriptions changed to reflect what was already unofficially the case in (most of?) the company. Roughly: you can hang at L4 pretty much forever, as long as you're willing to keep learning new things as required for your role.

That leaves the pressure of getting from L3 to L4, which, admittedly, people do feel. But L3->L4 is also a much more straightforward promotion. It's not nearly as sensitive to finding the right project/right team/right boss, and the promo comes more from your impact on the project than your project's impact on the product/company.