Obsess about the quality of the product.

If you pivot, do it fully and with conviction. The worst thing is to try to do a bit of the old and the new-it's hard to kill your babies.

At YC we have this public phrase, and it's relentlessly resourceful.

Don't let the company get distracted or excited about other things. A common mistake is that companies get excited by their own PR.

So if you want a culture where people work hard, & pay attention to detail, focus on the customer, are frugal: you have to do it yourself.

If you can just learn to think about the market first, you will have a big leg up on most people starting startups.

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