High quality giving more FPS against low quality on android?

I made an exampe scene which includes an turning cube in it. And changed its quality in runtime. Results are imressed me a little bit. I was expecting when i decrease the quality level gave more fps but results are different. When i was increased quality my fps increased. How thats happened?

Here is the full screenshots of what am i talking about:


I would think that there’s an fps limit when using lower quality. It’s a really useful thing, because if you have e. G. 70 fps then it suddenly drops down to 25 then you’ll notice a lag eventhough 25 fps is not that low.