It acts strictly according to the pre written rules of the contract, nothing less nothing more, it is 100% web decentralized meaning that there's no central point such as a company or authority in of control of the web contract. It cannot be stopped; it cannot be shut down and you cannot be banned from the program.
There are no limits to what a smart web contract algorithm can do, the smart web contract is there to simply perform the action it has been programmed to do when the contract requirements have been met, without the need of a third party or human intervention.