So sounds like you are one of the lucky folks who is excited and really enjoying their day job that you dont need a challenge after work. I once heard that those who are very stimulated at work actually spend a lot of energy and need cool down "after work". I (like many I know) can't wait to get home after a soul crushing day (at a pretty well paying job) to work on exciting things! Depends on factors that energize and motivate you I guess!