I just want to know whether google checks your site particulars when the pending amount from adsense exceeds certain limit?
I think they keep an eye on websites all the time to catch the cheats and members using unfair tactics to get clicks.
Nope, they watch every publishers earnings and out there lots of banned stories even they could'nt reach the minimum of payment because of fraud click..
There is nothing like any limit that needs to be exceeded however they have automatic alert system which detects invalid clicks based on certain factors. IMO, they manually review account which have exessive amount of alerts generated.