Not everything is figured out for you. You need to investigate, test, learn and iterate. You're selling a new product to a niche market, so if you're not a people person and persistent, the sales/support department is not for you.
There is obviously risk associated with working at a startup. If you're not a top performer, there is no place for you. If you don't put in the hours and work smart, you won't earn a lot of money.