Attrition is the clause in a contract that requires a group booking to commit to a certain number of rooms. It states that the guest is to pay for that specific room-block and should their numbers decrease there will often be a penalty charge to make up for the rooms no longer rented.
Attrition is also referred to as Wash or Slippage and is often considered a failsafe for hotels to ensure they do not lose out to fickle group bookings.
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