If the contractor fails to complete by the date for completion in the contract and if it is not entitled to an extension of time, the employer can claim damages. These are usually set out in the contract as liquidated damages, represented by a pre-agreed sum per day or per week. This is to save the trouble, time and expense of having to prove that a breach of contract has occurred, that the employer has suffered a monetary loss and the amount of the loss. Estimating liquidated damages must be done with care to avoid them becoming penalties and being unenforceable. The whole process generates many questions.