One reason is purely out of goodwill, to help someone out. Another way is to invest your money (which is basically what a lot of people end up doing today), thi

One reason is purely out of goodwill, to help someone out. Another way is to invest your money (which is basically what a lot of people end up doing today), this can be viewed as a form of lending, but with the possibility of making profit. So if someone wants to take a loan to start a business for example, you lend them money to own a portion of it, and hopefully get something in return. Basically what VCs do nowadays.