Remember that you are more likely to die because you execute badly than get crushed by a competitor.

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

I care much more about the growth rate of the market than it's current size and I also care if there's any reason it's going to top out.

If you look at successful pivots, they almost always are a pivot into something that the founder wanted. Not a random made up idea.

Here's a good rule of thumb: don't worry about a competitor at all, until they're actually beating you with a real shipped product.

No matter what you choose, build stuff and be around smart people.

In the early stage of a startup, hiring senior people is usually a mistake. You just want people that get stuff done.