You could say that no real estate purchase contract is complete without contingencies. These conditions allow the buyer to back out of the deal or go back to renegotiate it if certain events occur.
The importance of these provisions in your home purchase contract cannot be stressed enough. Even though you walked through the home and made an offer that the seller accepted, the deal cannot close until all due diligence is complete. During this time, you will more than likely find out just what it is you are buying, and you may not like it.