If you run an A/B Test, and the results are that there's no difference in your key metric, do you keep the experimental version, or revert the site back to the control?
Your client comes dashing into your office.
"I know what'll make this webpage POP! Change the product photo to a buff dude holding a beer, and put the call to action over his chest!"
"Umm...I don't think that really meets the needs of your users, and it doesn't fit with the theme of the..."
"My mother LOVES buff dudes!"
"Umm...ok, how about we A/B Test that, and see if it makes any difference."
So you run the silly A/B Test, and you're somewhat surprised to note that there's no difference. Would it make more sense to just implement the change request, or tell the client that it didn't actually help?