@thomasfuchs As I understand it, the metaphor was originally intended to include the idea that you have to take on debt to do big projects, just like you have to take out a mortgage to buy a house. But that's largely been forgotten. And when you take out a mortgage, you're not OMG, I OWE MONEY, THIS IS TERRIBLE--you think about the interest rates, whether there are better things you can do with the money you have, etc.