[dfee]

Is there reasoning to not drive this into the ground, I.e. where profitability for the campaign hits 0?

At a practical level I wonder if you / they are cognizant of an exhaustion measure, if new campaigns are introduced rapidly enough to continue to maintain a 5-10x return, whether the spend is managed to a predefined ROI, etc.

For what it’s worth, I’ve always seemed to drive it into the ground, but those are for short term campaigns. The long term campaigns I’ve inherited have usually already been driven into the ground before me (though the PE firm I was working for bought that distressed startup on the cheap).

[xstartup]

It depends on what you are doing. Many are just middleman, so they sell conversions they drive from FB, the difference of which is your profit. You have an incentive to keep conversion cost as low as possible and quality as high as possible to maintain your conversion payoff.

Driving it into the ground might be profitable for a product owner but not to an ad agency which pockets the middle.