I found this fascinating quote today:
If I think about all the issues we've had on wall street over the past year (see Michael Lewis and Daniel Einhorn's two part column for a great description of them), I think most of these issues have been caused by investors playing with other people's money without enough of their own net worth at stake. Financial leverage is a good example of playing with other people's money. You put up a tiny amount of your own money and you borrow the rest. If things don't go your way, you write off the little you put up and the lender takes the bath. That's been going on in the financial markets and the housing markets for the better part of ten years and we are now seeing the cost of that approach.A VC, Jan 2009
You should read the whole post.