Not spending all of your AdWords money for the month. Don’t worry. Google will spend it for you using words you didn’t approve. If you are told you are part of their new beta program, don’t be sucked in. Opt out. Now maybe this could be beneficial for some. You might even discover phrases you should be bidding on that are successful. I just object to the idea of being automatically signed up for an additional cost item that I didn’t approve. Yes, I did agree to a maximum monthly spend but it was also with the knowledge that I wouldn’t always reach my maximum spend.