I don't want to sound an asshole, but I will sound an assholle nevertheless. I was damn happy as one can be at 3.5 years in my career. 10 years in, I feel like my happiness and awesomeness has been slowly consumed by corporate politics, unfair promotions and layoffs, bad work ethics and the such. I still like my work. I really really enjoy it when it's productive, and I still feel amazed to see the green checkmark on…
The thing I relized that is helping a lot is doing stuff that a) builds on my interests and experience and b) is a intellectual stretch.
Otherwise I run the risk of being bored and running out of patience with the politics around me. Lucky me for now this working out okish to fine sometimes.
Ah, and having colleagues that a fun to work with!