So, I'm trying to wrap my head around this. In order to be like Snapchat[Facebook|Twitter|and the like], you must defer monetization. But when you're starting up, cash is scarce and you need money ASAP. Since you can't always depend on getting external funding, you need to charge customers early.

How do you start a business if you can't convince investor to put money in, and not allowed to receive money from customers?