Really, The process of ad sense approval is more complicated one. We can get the ad sense approval from google only after full verification process of our application is completed. The document what we are submitting for ad sense approval should be more reliable and informative. Before apply for ad sense approval, We should learn various terms and conditions of google ad sense. It will help us to avoid our application to be disapproved.
There are various status for applications available in google ad sense like Pending, approved, disapproved. The pending of approvals are in process and further it will be approved. The disapproved applications are required more attention to verify our submitted information to google.
The minimum requirements also to be satisfied by us to get approval from google ad sense. For more details, you can refer the ad sense profile of yours. We should satisfy 5 out of 6 requirements in that.
Sometimes, The ad sense account may be disapproved after a long time it is approved. This will happen due to illegal access and "Invalid click access" in our account. This will affect and reduce the revenue of the members of this ad sense. If it is happened once, The google will disapprove our account. Once it is disapproved, then it is difficult to get back the same account again and some times it is not possible also. While the account is being disapproved, The balance amount in ad sense will be automatically canceled and we can't get it back. Then only way is that we have to create new account with ad sense again.
So, Please take at most care while handling the google ad sense account in future.