The preview feature in the bulk task definition isn't displaying all the accounts that meet the filter criteria, causing some accounts to be excluded from updates. This leads to inconsistencies in the user store, where some users are updated while others remain unchanged.
Bulk Task Definition can't be used when the search results are incorrect and inconsistent. We end up updating non-eligible users due to incorrectly returned results.
Identity Manager 14.5.1
Engineering team provided a hot fix to resolve this issue as part of defect DE646937. If you face the same issue then please create a support ticket and request for the fix.