Execution Not Ideas
It's almost comical how many times I talk to a new entrepreneur who has a billion dollar idea. It's usually something like Uber for dogs or Twitter for millennials. Or it's a dating app that "really" works (don't most work? maybe, just not for them).
In reality, most ideas are not new, and most of the work is in the execution. Paul Graham said it best:
"Actually startups take off because the founders make them take off. There may be a handful that just grew by themselves, but usually it takes some sort of push to get them going. A good metaphor would be the cranks that car engines had before they got electric starters. Once the engine was going, it would keep going, but there was a separate and laborious process to get it going."