What's up with the "Outline Object" effect?

I'm trying to understand how it works with little to no success. My mind tells me it's basically "Expand" but non-destructive, yet I can't get it to do anything. I looked for some help online and found old community posts and videos where they use the Outline Object effect on text, but it doesn't seem to work anymore. The only thing I managed to do with it is add an outline to an image, which is honeslty not that useful. What else am I missing?

I managed to get Outline Stroke to work, in which, yes, it works like a non-destructive "Expand", and other effects like Roughen will apply differently.