Working more than 8 hours a day, makes my unproductive

debingjos writes: Our management seems to thing that our devs can get extra work done if they work extra long days. However, as one of the devs in question I don't agree. When I've been coding for 8 hours my pool of concentration is exhausted and working overtime does not get a lot of work done or the quality is very bad.

What is this communities oppinion on this?