It's usually due to incentives and the time horizon you're optimizing for. If a manager is tasked with maximizing revenue over the next 12 months no matter what, then increasing the ad load is a lever you are probably going to pull.
If your goal is to create an enduring product that will slowly grow revenue and be around forever, then you're probably not backed by VCs or private equity, or you have a cash machine (google search, etc).
The reality is that some businesses shouldn't take VC money and shouldn't get so big. Maybe a wiki farm should just be a wiki farm profitably run by 5 friends or something.
If your goal is to create an enduring product that will slowly grow revenue and be around forever, then you're probably not backed by VCs or private equity, or you have a cash machine (google search, etc).
The reality is that some businesses shouldn't take VC money and shouldn't get so big. Maybe a wiki farm should just be a wiki farm profitably run by 5 friends or something.