Recently, a lot of publishers have been getting their accounts disabled for "fraudulent or potential fraudulent click activity."
This has frustrated a lot of AdSense publishers because many claim they have done nothing wrong and how in the heck does Google define "potential" click fraud?
No one really knows.
Remember, Google earns most money from advertising. The ads that appear on your pages are costing someone money every single time a click is registered.
Google monitors clicks very closely -- especially if your account is new.
So if they sense A-N-Y-T-H-I-N-G out of the ordinary or feel you are getting traffic from places that may may produce bot/automated/fraudulent clicks, they will disable your account to protect their advertiser's money.
They used to disable when they confirmed fraudulent clicks, but now they will disable even if they see potential risk with your account -- whatever that means.
Then they refund the advertiser their money -- which is why you don't receive a check for money earned if you are disabled.
And to make things worse, their communication when you are disabled is automated and there are usually no warnings -- which is unfortunate and frustrating for people who have done nothing wrong. There's also no way to reach out for definitive answers and appeals usually fail.