Dan says the vast majority of junk mail - be it loans or otherwise - is directed at the sub-prime market: "The best thing you can tell a client is that you can accurately identify sub-prime individuals. Which is why, when people are asked to fill in lifestyle surveys, they'll often see questions like, 'Have you ever experienced difficulty getting credit?' or, 'Have you ever missed a mortgage payment?' Those are the sorts of triggers that will identify you as potentially sub-prime."
So an inability to pay debts wasn't merely a flaw to be overlooked, but something that was actually desirable in creditors. More to the point this was generally known before the bubble burst.