It matters greatly if you're entering a thriving market, or a graveyard market (one littered with tons of failed attempts and no reasonable success stories). I

It matters greatly if you're entering a thriving market, or a graveyard market (one littered with tons of failed attempts and no reasonable success stories). If it is littered with failed attempts (turning one's future personal income into a security, for example), be extra extra extra careful. There's a reason so many people thought it was a good idea, if they all failed then there's probably a reason they all failed too. The dangerous problem with entering a graveyard is that the reason the market fails is probably something you'll figure out in year 2 or 3 as you're shutting down shop, not something you'll find in your first month of trying.