>>174
A lot of reasons. Being sick of PHP was one of the major ones.
Another major one was constant service to help the people who used kusaba to host a direct 4chan clone, who knew nothing about MySQL/PHP and barely could get the thing installed without my help, let alone maintain boards with it.
After a little experience with Python and a lot more with Haskell (which is my new favorite language) I just can't bear to write PHP any more without thinking "I could do this so much cleaner/easier in Python/Haskell".