In an illuminating and predictably controversial exposé for This American Life, NPR’s Planet Money team tried to figure out why, since 2009, nearly 250,000 people have been applying for disability every month (while we’ve averaged only 150,000 new jobs every month).

The answers fall on both sides of the gray middle.

One factor has to do with what correspondent Chana Joffe-Walt calls the “Vast Disability Industrial Complex.” These are the sometimes shady, sometimes well-intentioned lawyers who fight to fatten the rolls of disability recipients. These lawyers get a cut of every winning claimant’s “back pay.” The more clients, the bigger the take. That’s why they run ads on TV shouting, “Disabled? Get the money you deserve!”

Then there are the doctors. Joffe-Walt profiles one rural Alabama doctor who signs off on disabilities for pretty much anyone lacking a good education on the assumption that their employment prospects are grim.