As soon as a customer deletes a Mac device from his account, it is automatically moved into the so-called "Decomission" pool and then completely deleted via the MDM server using an Erase command. With this action (only possible via MDM) everything is completely deleted. Even the disk partition scheme and all including volumes are securely erased. Afterward, a fresh macOS installation is automatically initiated and then moved to the general "Available" pool. This cycle ensures that no residual information and data remains from the previous customer.