Hi Akhil,
When you use a forward mailbox there is an option that you can select to delete messages after the messages are processed, this way you can keep the mailbox to a minimum all the time.
The forward mailbox is also know as a sink mailbox and from an admin point of view you have greater control over this, so even if you don't want to delete the messages automatically you could manage/monitor the central mailbox as you wish.
Hope this helps.
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