When should avatars or profile pictures be used in a application?

Designing a new application and wondering when avatars or profile pictures should be used.

e.g. Let's says there is an application which can be used to manage a list of user tasks. Each task is assigned to a user.

There will be a list page which displays all the open tasks and when a task is clicked it will take the user to the individual task details page.

Should there be an avatar on the list page for every task item? or is showing the users full name enough on this list?

Should there be an avatar on the individual task details page? or is showing the users full name enough on this page?

What benefit do avatars or profile pictures give when viewing a screen as opposed to showing the user name only?