"Then you start looking for a new job and realize it's back to the books for you"

As a designer still trynna find his feet, Godddd!!! this is my biggest challenge, I left working for startups because I wasn't getting any mentorship or growing like I wanted to and had to fail at everything on my own until I became better. After leaving my last job and trying to get a good UX design job at any already established firm, I realize there are stuff I have missed learning on while working at startups and now it's just really hard for me to go back to the drawing board and learning all over again. I even decided to take Google's UX course and I always fall asleep minutes in because a lot of everything they say is already stuff I've grown past.

Depending on the situation, it really not advisable working for startups, especially for people still young in their careers