Access to application: Users&Permissions vs. Share

Access to application: Users&Permissions vs. Share

Giving access to user through Users&Permissions is preferable for me. I also understand that rules set in Users&Permissions override Share permissions, if used simultaneously.

Question: After I added a user into Users list and assigned role and profile to him, why this user still don't see my application in his account? even with link to application, he doesn't have access.