For example, instead of rationally evaluating what sort of mortgage payment you can actually afford, why not take a plunge and buy a $600,000 house? You only live once, right? And instead of making your current dumpy vehicle last another year or two, why not take out a huge loan on a brand new $60,000 SUV? You know you deserve it. While you are at it, why don't you go on another huge spending spree and max out all of your credit cards again. Paying off those credit cards will be very painful in the long run, but nobody thinks much about long-term consequences these days.
Just look at the federal government. They are 28 trillion dollars in debt and yet our politicians continue to throw money around like a bunch of drunken sailors.