In a decently negotiated contract there are strict time limits included. But this is not always the case. People need to watch out when negotiating. The process goes a lot more smoothly when the details of this possible penalty are described in the contract.
Another example: Some smaller jobs are sometimes done without contract: for friends or worse, to avoid taxes.
As owner it is impossible in this situation to have control of the time schedule.
Climbing the BB-mountain. Destination: the top.