Can you recount situations where you made yourself miserable in the present for a future reward?

I am curious to know the times and situations that you have purposely made yourself miserable through effort, work, patience, or some other means in order to reap some future reward. What were you putting yourself through and how bad was it? What were you hoping to get out of it? Was the misery and suffering worth the wait of the reward, or did you either fail to achieve your goal or got something other than you expected? Thanks for sharing your life and experiences with us.