1. If you blog about something it's a good as a go to source in future, be it programming problems you have to solve again or arguments on the internet (here's one I prepared earlier).
2. It improves your writing, particularly technical writing, something developers are notoriously bad at. Written communication is just as important as coding chops for most developer jobs, sometimes more important.
3. It's a good outlet for whatever is frustrating you at work. None of my friends are developers so my old man rants (a skill is still in it's infancy for me) are lost on them.
Edit - The spelling mistakes indicate I still have room for improvement.
2. It improves your writing, particularly technical writing, something developers are notoriously bad at. Written communication is just as important as coding chops for most developer jobs, sometimes more important.
3. It's a good outlet for whatever is frustrating you at work. None of my friends are developers so my old man rants (a skill is still in it's infancy for me) are lost on them.
Edit - The spelling mistakes indicate I still have room for improvement.