The check out is an inspection at the end of the tenancy.
The purpose of the check out is to determine if the tenant has caused any damage (or change where permission was not granted) to the property which requires financial compensation. The property should be handed back to the landlord in the condition it was given to the tenants, with an allowance made for fair wear and tear.
The check out report will note any differences in the condition of the property from the inventory report. It will also indicate whether the difference is due to fair wear and tear, damage by tenant, due to maintenance or needs to be cleaned.
It is for this reason that a well-compiled inventory is so important as the check out report can only be as good as the original inventory.