If you compromise and hire someone mediocre you will always regret it.
Once your product is working, switch from not caring about this to caring about this a little bit.
So you should always stay on top of people's vesting schedules.
In YC's case, the number one cause of early death for startups is cofounder blowups.
If you don't love and believe in what you're building, you're likely to give up at some point along the way.
Wait to start a startup until you come up with an idea that you feel compelled to explore.