"promotion is more about consistent level N+1 behavior, while one could get a high performance rating by solving many level N problems." Not all companies are like this, and I find it common that new employees are not sufficiently taught what their company is like : A) you have been performing well as N,promotion means "we feel / hope you're ready to work as N+1 in the future " B) you've done great as N and have repe…
As others have responded, there are definitely trade offs with different models. The way I've seen (B) worked well is:
* Given a project, separate out the "level" of different axes. A project could have level N technical scope, but level N+1 collaboration scope, etc.
* Let the level-N engineer handle one level N+1 axis at a time, with supervision on other axes.
* And if they ace one axis, then back off and give them more responsibilities on the other axes, for the same project or subsequent projects.
Of course there are also scenarios where someone is just thrown into the deep end. They will either sink or swim :)