Epic doesn't care about any particular product or service. They are a publishers with aims to become a storefront, but plan to do so by passing off customers and devs and partners.
I really don't understand how on one hand all of these CEOs and investor types are geniuses and just built different but on the other hand they're hiring people and firing people because they couldn't predict the line on graph doesn't always go up.
If I had to guess, it's because of money. There was more incentive at the time to grow fast and try to maximize profit than to limit growth and potential profits in case of a market downturn. Tim slightly explains what happened.