They also suggest you use oil when trying to fry things. You just use a lot less oil when you do.
But if you try frying, like, french fries in an air fryer, even with some spray on oil, it doesn't come out the same. It comes out like they were baked. If I wanted them baked, I wouldn't have used a frier.
Yours probably just isn't great. Some you need to let preheat, some just aren't very good. I've always really felt like food comes out of air friers nicely fried, with no oil.
I have a Ninja. It's not great for frying because they don't actually fry anything. They're convection ovens. It's better for the pressure cooking features than the so-called frying.
Yes, they accurately do not fry things, that would be magic. They do make them crispy though. Most Americans don't have convection ovens, so air fryers are as close as wet can get, and they usually do work well. Sorry yours isn't working well for you, apparently.
I can make them crispy the exact same way by baking them in my normal oven. There is still a textural and flavor difference between that and deep frying. It's not that my device does not work well. You may like it; I fucking don't and looking at the comments, many others also don't like the difference.