This. I started my company in my early 20s and had no clue how much work it would be due to my own naïveté. Indeed, we broke the problems down and worked through them one-by-one until we had a functioning business model. On the one hand, it would be a lot harder to start over knowing what I know now about how much work it takes. On the other, it would be a lot easier because I got a lot better at problem solving and decision making.