Years ago one of the top mentors I ever worked for noticed that I would regularly be putting in 10 (or more) hours a day. I was young and enthralled with technology and I had gotten into a bad habit (yes, bad habit) of thinking that my efforts to improve things (software, hardware, databases) was "work". He asked me if I thought that the hours beyond 8 a day were really productive. My off-the-cuff answer was "Yes, of course", but talking further with him, and thinking about it, I realized that what I was doing was more often than not, simply creating more stress and conundrums for myself.
This respected mentor taught me a great system which has been my work strategy for the last couple decades - prioritize my tasks into simple categories of A, B and C. "A" being the things I had to get done, "B" being the things I should get done, and "C" being the things I would like to get done. In adopting this strategy I learned something a bit astonishing - the "extra hours" I was putting in were not very productive and usually they were stressing me out over the "C" priorities - things I just would have liked to get done - they were not crucial, not business-critical.
In the years since I have worked mainly 8 hour days. I have learned that problems I cannot solve in any given day are still there the next day, and if I dicipline myself and get rest, most often those solutions come easy the following day. Indeed, now that I manage young programmers and engineers, when I see them worn out fighting over some challenge, I tell them "Go home, it will still be here tomorrow, but you will be fresh." I think a few of them have learned that that is the key to productivity.
It all got driven home solid a few years ago when one of my peer executives, a guy who stressed over everything and worked some 60-80 hours a week simply dropped dead. He was on a business trip, and one morning simply didnt wake up. A Heart attack killed him in his sleep, leaving his two kids fatherless and his lovely wife a widow.
I work 8 solid hours a day - 8 productive hours a day - and day after day work gets done. No, the businesses are not perfect, but they are doing very well and I realize that extra when required are fine, but dont necessarily push anything more toward perfect. Business is never perfect.
Bottom line? I've seen plenty of people work way too hard thinking that someday a retirement will come and they will have lots of money to "rest". Thats baloney. Few ever see it and those who do usually are stir-crazy in retirement. Do your 8 hours a day and work hard - but remember business is like a river and there is always a flow coming at you - sometimes heavy, sometimes light, most often something in-between. But killing yourself in technology, a business that is always changing, is not worth leaving your loved ones without you.
There's no such thing as dumb questions, only poorly thought-out answers...