98% owner. To me phone verification is a fucking joke and not worth the money or time considering the numerous problems and ways to bypass it. Depending on the script you use, it will filter out most known proxies but misses a lot of them and is not very good at catching the fresh proxies.
And that's just the half of it like jeffrey said. You then having people signing up with complete made up shit or addresses picked from the phone book. You then have them duplicating the same offers on other sites. You then have them using fucking gibberish and bullshit information on the offers they complete. You then have them signing up with multiple accounts doing the same offers again. I could go on and on.
You either don't care and go with the attitude "as long as I get paid" or you spend countless hours combating the shit you can. And it doesn't matter how good you think you are, you will get burned here and there but you will
pick up the numerous patterns and ban the stupid fucks and laugh at their "I didn't do anything, u a scammer" complaints.
EDIT: And I agree with jeffrey when it comes to most of these kiddies starting a gpt site. You have no fucking clue what's involved and think it's gonna be a 'get rich quick scheme' and then you crash and burn and can't even sell it for 1/2 of what you paid for it.
I'm not bashing the ones that want to start one, but good fucking luck.