Hi,
For Request Items and Catalog Tasks:

• Closed Complete – The work is fully done and all tasks are completed successfully.

• Closed Incomplete – The work could not be finished due to missing info, customer not responding, or the request becoming irrelevant before completion.

• Closed Skipped – A task or step was not required (e.g., workflow condition skipped it, or it became unnecessary).

How they are set:
These states are usually set by workflow transitions, business rules, or task closures. The workflow logic determines whether a step completes, fails, or is skipped. Catalog Tasks closure can also drive the RITM state automatically.