Because it's too easy to corrupt and/or destroy your geodatabase.
Because the password for the SDE user should be closely held.
Because the SDE user should be limited from too much permission
while running as a service.
Best practice is to establish one or more data ownership accounts, then
use roles to grant necessary accesses to other login/user/schemas,
so that only the minimum necessary permissions are granted to
non-owners.
- V
