Shortly after the launch of the Yahoo/Bing search alliance, I was notified by my account managers about a new and exciting feature, called "ad optimization". In a nutshell, this feature resembles Google's "Optimize for clicks" where the ad with higher CTR% will gradually be favored.
This is not an opt out feature which means advertisers are left at the algorithms mercy. I have struggled with this the most. Call me crazy, but I'd like the freedom to choose which ad I want to display the most. In my vertical, CTR% matters little. Instead we're looking at metrics like conv., conv. rate, cost/conv., conv. value etc. Thus, we always do A/B testing, running our ads at 50/50 for some time to accurately determine which ad actually outperforms the other.
I'm a little surprised this hasn't gotten more pushback from advertisers, can't really seem to find a lot of discussion or news about it.