A month or two ago, GAW changed the policy. Previously, overcharges would be modest (a few percentage points per day). But now, it can go over as much as double or triple. Yes, triple. For some of my clients at $200/day, they can see $600 in one day in charges.
GAW does this because on weekends, clicks can be low, so over the week, the extra clicks make up for the lack of clicks. All in all, you get maximum clicks (and billing). At the end of the month, if there are overclicks, those are deducted. You got those clicks for free.
But this brings up another problem. On July 19th, for several of my clients' accounts, GAW "adjusted the overclicks" by turning off the accts for a day. Zero clicks. They did that to keep the acct within budget. But... that's a very bad solution. For a company, it's not amusing to have zero sales. The store costs (rent, staff, etc) are the same, yet there are zero sales.
GAW should not use zero-click days to balance accts. If they overdeliver, then they should either balance this with low-delivery days or take the loss and give credit to the store. But they definitely should not stop ads for a whole day.
That definately would be unacceptable. I haven't had that happen to any of our accounts yet, thank goodness.
By any chance, did those "off" days follow major changes in the ads or keywords of the account?
I've noticed that $G is pretty slow to adjust delivery in response to sweeping changes.
Freq---
When Google says you won't get charged more than your daily budget they really mean this:
Say it was July 2005 (31 days) and your "daily" budget for all of July was fixed at $100/day...
For the month, that is $100 x 31 days = $3,100 for the month. Google is saying you won't get charged more than the $3,100 for the month.
- Many times AdWords will automatically adhere to your daily buget setting quite naturally, but I have seen cases where he went over the daily amount by a considerable amount for an entire month. In one of these cases, Google credited the client for the over charges before ever billing the client's credit card.
I've emailed back and forth with our dedicated reps about this. Perhaps they'll not do this anymore.
Watch your stats and if you see a day that has zero traffic, you'll know what happened. We need to emphasize to Google that they can not use this solution.
I confirmed this some time ago; indeed, I even "played the system" for a little while by launching campaigns with $0.05 bids and daily budgets of $0.05 for each campaign. The result was that Google would generally overrun my campaigns by 30% or so (on average) and would credit that back at the end of the month, so my cost per click was actually less than 5 cents. I was only running a dozen or so campaigns, and did this mostly to just see whether Google would balance things out properly -- but I could envision someone really using this to abuse the system, if they launched thousands of nickel campaigns with nickel budgets.