M&A negotiations feel really fun. This is one of the biggest killers of companies, is they entertain acquisition conversations.

Most good founders that I know at any given time have a set of small overarching goals for the company that everybody in the company knows.

Once your product is working, switch from not caring about this to caring about this a little bit.

You also want people who are maniacally determined and that is slightly different than having a risk tolerant attitude.

Before product/market fit, your only job that matters is to build a great product.

If you have several ideas that all seem pretty good, work on the one that you think about, when you're not trying to think about work.

The most common post YC failure case for the companies we fund, is they're incredibly focussed during YC on their company... and after they start doing a lot of other things. They advise companies, they go to conferences, whatever.