Instead of waiting for something to go wrong and then conducting a post-mortem, conduct a “pre-mortem” by imagining it went wrong then using the power of hindsight to deduce the likeliest reason it went wrong.
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.