You notice that some user accounts are missing from search results when:
- You run an API query to the /people endpoint
- Checking the list of users in the Admin Console's User Search
This may happen when users are provisioned via LDAP or SSO (e.g. Microsoft Azure AD).
You may find that you can find the users when searching by certain attributes (like email address) but not when searching by other attributes (like the users' names).