As is known in the Microsoft Exchange database size after removal of the mailboxes is not decreasing but remains the same.
Created the database “gap” so called White Space which tells us about the amount of available space, which can be used without the need to increase the size of the database file .edb.
Only after completing the White Space, a further increase in the size of mailboxes in the database, it will increase the file size .edb file.
In the case of Microsoft Exchange databases such solution is problematic, because in order to reduce file size .edb after removing mailboxes from the database we use the most with ESEUTIL, which have performed defrag the database.