According to Build engine's author[0] this is why he created his own license
instead of using the GPL.
> Short answer: to satisfy my ego :) Long answer: I know GPL is an industry
standard, but I felt that it was way too long and boring for anyone to read
seriously. I chose to write a nice short license that everybody could
understand. This way, people unfamiliar with GPL would understand their
rights.
It's seems like he misunderstood not only the GPL but free software in
general (I'm guessing it would have been "too long and boring" to learn about
it). Apparently he thought the important takeaway of "open source" is the
ability to look at source code and use it for limited hobbyist non-commercial
use.
[0] http://advsys.net/ken/buildsrc/
