Last time I looked into it, it looked like a bad wager unless you're a military pilot. Starting pay isn't great, building hours on your own dime is expensive and you're always once bounced physical away from the unemployment line. Virtually no airlines last I looked had training programs, relying on the mil pipeline. So, it's entirely possible to get an insanely huge amount of debt and then be downchecked at any second due to high blood pressure or whatnot. I doubt you'd get a refund on all that debt and flight hours.
Bob hit the nail on the head.