When I was in my late 20s and early 30s I worked all the time - I loved it! At some point though I became disillusioned with work. There was always more of it, and it was primarily for someone else's benefit. If you're working for yourself I can see a stronger case for putting in those hours, but you still risk seeing those years go by in a haze of largely undifferentiated time sitting behind the keyboard, or what have you, with likely little reward at the end. It's possible to have a work-life balance, still enjoy your job and be productive, take vacation, etc. Work can become a soulless endeavor, just as pursuing wealth for its own sake.