There used to be a time when all we had to have to work was at one place: the office.
Time passed and now, all we have to work is still in one place: the Net.
I'm confortable at home, after working in the morning and going to university in the afternoon. Now I'm working, again. I have to accomplish that 40h/week schedule.
You see... 40h at work + 36h studying = 76h/week completely occupied. If you take a week as 7days * 24h = so you have 168h. I have already used 76 of these, so there's 92 left. I use 14h to eat (all meals!) every week, so I have 78 left. I have to take at least one shower every day... Let's say that's another 1h, I have 77h left. Do you drive to get from one place to the other? I do. I'm lucky they're near... Let's say I spend 2h a week to go from home->work->university->home. I have 75h left. Do you sleep? I do (at least I used to...). So, there's 7days*8h (56h) less. There are 19h a week... I need to buy food. 2h a week at the market (includes driving to it too). There are, then, 17h. I'll stop here... I've already gotten to the point: a day has 24h. I don't even have all the Sunday free to rest!!! And, of course, I need to study, so forget about these 17h free a week.
Now, back to work...