This thread is full of personal stories so I'll add mine. Writing software is fun but burned out on doing it professionally for 10 years. Frustrated I was just making my bosses rich and building their dreams not mine. Frustrated at programming's long-term career trajectory (Nobody will hire you after 40). Dreamed of doing my own thing but no capital to start a company. Went into debt for an MBA, goal of getting into finance or somewhere without tech's various career limitations and "ceilings." Graduated from highly ranked MBA school. A month later Lehman and Bear explode and suddenly nobody is hiring MBAs (oops!). Back to programming. Programming is still fun, but I continue to just making my bosses rich. Moved into product management thinking it will be different. Still no career trajectory. Moved into project management. Still no career trajectory. Made it to 40 and still have a job but no capital to start a company. Still figuring out what to do when I grow up.

Lesson learned I suppose is you can change your role, your industry, your company, but it doesn't change the fact that you'll be stuck on the burnout treadmill building someone else's dream.