his exposure is he thought he could be partner but gave up and just dreaming of the could have would haves if he stayed on.

in seriousness, the learning curve never stagnates in big 4 if you are worth your salt. i've lasted for 6 years and there always something new to learn

so many industries, so many people to interact with, and you get to see how management views their business, can be the same industry but two different schools of thought. can be same accounting issue but different treatment. really trains your problem solving skills outside of just being technical or good at accounting, and over time your client will trust you with solving their problems even outside of accounting.

but all this being said, learning curve is something people arbitrarily put on their jobs. im sure you hear people saying xxx career is garbage there is nothing useful, can be audit can be FP&A can be internal audit, there will always be someone who says that you will stagnate and whatever bs.

i moved in FP&A against the advice of some of my partners (some not all, some give genuine advice) saying that after a while you learn nothing. its all bs, i still learn as long as i put myself up for the opportunity.