By default, this option is not selected. If unchecked, the PMS will switch the Housekeeping status of a Room to ‘not clean’ upon check-in. This status is set once by the PMS, if the user changes the status during the stay it and will remain at the status set by the user (until it is changed by the user).
When the setting is checked, each room that is check-in will be set to Housekeeping status ‘not clean’ overnight. So each night at midnight all checked-in Rooms will be set to ‘not clean’, regardless the possible status changes made by the user. This will result in the rooms to appear in the Housekeeping overview to be cleaned.