Outlook integration for contacts: are deletions only sync'd one way?

Outlook integration for contacts: are deletions only sync'd one way?

When I delete a Contact in ZCRM it is also deleted in Outlook Contacts (which is good).

But when I delete a Contact in Outlook Contacts it is NOT deleted in ZCRM.

Is this deliberate? If so, can you explain it to me please?

Many thanks

Steve