I'm a newbie to CPA marketing and i have a question about Facebook ads and CPA offers, When do you determine to kill or scale a CPA offer? Is it after $3 spent and no conversions? is it after 2-3 days and no conversions and CTR below 5%? Is it after 1 day with no conversions? HELP!!! I'm looking for a system to determine when to either kill or keep CPA offers via Facebook ads.