Comment by akdas

One thing that I've seen implemented to prevent that is to have the pay bands for level N and N+1 overlap. So in the time that you're doing "next level" work, you're expecting to be at the top of your current pay band, and then the promotion doesn't automatically give you a big pay raise, but it unlocks a pay band that you can go up in.

This works if performing at the top of your current level equates to performing at the bottom of the next level. That said, there's a problem where sometimes a "promotion" is really a new role, meaning to perform at the next level, you have to kind of not perform well at the current level.