It is a numbers game, especially if you're hiring for straight commission 1099. Unless you figure out some magic formula that no one else has, you'll go through 10 to 20 to find one keeper.
Here are the sad facts, at least as I see them. 95% of the people in the world who call themselves sales people are horrible. They're lazy, unskilled and they do absolutely nothing in terms of practice or self education to improve themselves. Do high school, college or pro athletes just show up for games? Or do they practice, study game film and do other things that help their skills 5 to 20 hours (or more) for every hour they play in competition? Why then do people who expect to make their living expect to make $100K by going out selling 20 to 30 hours per week?
So you ask, how can those 95% survive? Very simple. Because the majority of the time, they're competing against the other 94%. In most cases, the buyer purchases from someone despite their best efforts to lose the sale.
Then there is the 5%. That 5% is comprised of those that have some level of skill, some level of dedication and a reasonable level of work ethic. And they have some level of passion. None of the 5% have all those attributes combined though. And then you have the 0.1% that have passion, their work ethic is superb, they have good to great natural skills, and they bring that all together by constantly seeking out training, reading books, etc.. That 0.1% are called Rainmakers.
If any of that 95% runs up against a Rainmaker, they are wasting their time. They have no chance whatsoever. For the most part, that is true if they try to compete with the 5%. Occasionally, one of the 5% may pull out a win against a Rainmaker, but not often.
So there you go. 5% is 1 in 20. So you have a 1 in 20 chance of finding one of the 5%. 0.1% is 1 in 1000. That's your odds of finding a true rainmaker.
So what do you do? Try to find some of the 5%. Try to at least get 95%'ers that have a good attitude and are honest. Have a solid process in your company. Advertise wisely. Unless you're different than most owners, if you somehow ever get a Rainmaker, you'll likely lose them because you'll get greedy and never want to pay them what they're actually worth.
I hope that helps.