Deleting users with exchange accounts in AD Manager

Deleting users with exchange accounts in AD Manager

I have an interesting issue. When I am delete users out of AD Manager that have exchange accounts it is marking the last update in AD for that user as an exchange user. I noticed this when a ran a recently deleted user report out of AD Audit. The accounts I am deleting are showing as an exchange account instead of my username. Is this by design or do I need to not delete the exchange accounts when removing users from AD and manually go to the server to remove them. See attached image. I removed this user out of AD through AD Manager as you can see the caller user name does not show my username but an exchange account on one of our exchange servers.