Too Long; Didn't Read
The most important thing I learned from a billionaire I worked with, that you need to know. The most profitable thing you can do is to sell more to your current customers. You need to have a strategy for selling them more once you’ve already brought them in, because those secondary sales are pure profit. On the first sale, you're losing a chunk of it to your marketing costs. The kind of mentality that caused my first company to fail. That will lead any business to failure. It wasn’t until years later that it really sunk into my head.