Duplicate task names can lead to erroneous behavior.

Document ID : KB000126416
Last Modified Date : 08/02/2019
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In theory it is possible to have two "admin tasks" with the same name.  For example; where on task is assigned to Identity Manager and the another is assigned to the Identity Portal.

2 Admin Tasks 1 Name

Even if the tasks have some subtle differences in content, for example different Tags or "Hide in Menus" checked etc, some erroneous behavior may be encountered.  One scenario encountered in deployment saw some Roles with missing tasks.
CA Identity Manager 14.x
CA Identity Portal 14.x
CA Identity Suite 14.x
Some of the background code which calls the tasks is reliant upon unique names.
As a best practice users should avoid creating duplicate task names.