Joel Spolsky:

What drives me crazy is that ever since my first job I've realized that as a developer, I usually achieve about two or three hours a day, on average, of productive coding. When I had a summer internship at Microsoft, a fellow intern told me he was actually only going into work from 12 to 5 every day. Five hours, minus lunch, and his team loved him because he still managed to get done a lot more than average. I've found the same thing to be true. I feel a little bit guilty when I see how hard everybody else seems to be working, and I get about two or three quality hours in a day, and still I've always been one of the most productive members of the team. That's probably why when Peopleware and XP insist on eliminating overtime and working strictly 40 hour weeks, they do so secure in the knowledge that this won't reduce a team's output.

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Many of my days go like this: (1) get into work (2) check email, read the web, etc. (3) decide that I might as well have lunch before getting to work (4) get back from lunch (5) check email, read the web, etc. (6) finally decide that I've got to get started (7) check email, read the web, etc. (8) decide again that I really have to get started (9) launch the damn editor and (10) write code nonstop until I don't realize that it's already 7:30 pm.

Somewhere between step 8 and step 9 there seems to be a bug, because I can't always make it across that chasm.

I so have that pattern. Then I talked to the guy next to me who I consider a really diligent worker, and he has it too. I wonder if what I do for a living is really mentally exhausting, or whether I just have one of the most slack jobs in the world. I have a feeling it's somewhere between the two.