The "run a task whether the user is logged in or not" [1] simply makes the task being run as SYSTEM user, rather than your own user.
Given that you are not the SYSTEM user, the program will never appear to you, but it will still run. source
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Setting to run an app every hour after midnight, for 7 hours
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When this task triggers, it will only execute if the statement "the computer has been idle for 10 minutes" is true. The task will wait up to 1 hour for the statement to become true, and then it will give up. source