Marc Andreessen, who wrote: “The world is a very malleable place. If you know what you want, and you go for it with maximum energy and drive and passion, the world will often reconfigure itself around you much more quickly and easily than you would think.”
You can be the best product for small market, build a real company, and then from a position of strength, either stay there or attempt to expand to adjacent markets.
Or be undistictive in a huge market, out-advertised and invisible, never getting off the ground.