Since at the time I was quite happy with Python, I'd have to say that I learned Perl more or less at gun point. I'd looked at the books on the subject and more or less decided that Perl uses too many characters for my taste---sort of an ASCII APL was my impression. Got a phone call that pretty much said work was available (in Perl), which at least got me started. I was hooked even before I finished the site in question. If Python can be thought of as a pair of Italian hand made shoes, then Perl is a pair of well-broken in penny loafers. And frankly I much prefer the second to the first. They are both great languages, I just find Perl to be far more comfortable and a better fit for the way I think.
in reply to Why I learn a language.
"Never try to teach a pig to sing...it wastes your time and it annoys the pig."