How accurate are AI checkers?

I’ve been a movie reviewer for a couple of years, and occasionally people assume my reviews are AI-generated. The thing is, I’ve spent years developing my writing through extensive reading, English classes, and a lot of practice. Because of that, my writing tends to be polished and structured, which I think may be why some AI-detection tools flag it. What I’m curious about is how accurate these AI detectors actually are. Some people have compared my work to AI-generated writing, and when I’ve run my reviews through different AI checkers, I get completely different results. One detector might say a review is 100% AI-generated, another might say 70% or 80%, and another might classify the same review as entirely human-written. Some call it AI, some call it human, and the results seem to be all over the place. None of my reviews are AI-generated. Every review I’ve published has been written entirely by me, without using AI to generate any part of the writing. I just don’t understand how the same piece of writing can receive such wildly different results depending on which detector is being used. Are these tools accurate in any way, shape, or form?