Repatriation cover comes as standard on most travel insurance policies. In the event that you fall ill or are injured on holiday and you are unable to get the level of treatment you need, then repatriation cover supports you by covering costs should it be decided that the best course of action is to bring you or a travelling companion home to continue treatment.
The decision could be made because of the treatment required being available more readily in the UK or because the cost of treatment may well be cheaper in the UK. This could be particularly true if you fall ill whilst travelling in the United States.