“Most startups fail because because not enough people show up on the home page, or people show up but they don’t try the product, or they don’t pay for the product, or it’s too expensive to get them to show up, or they don’t tell their friends to come along, or because it’s not solving a pain that people have, or it’s not solving a pain that people know they have, or it’s too hard to explain the pain, or a bunch of other things that are not whether the code works or whether it looks good.”