You read it in the forums, in reviews and experience it on your own - stairs climbed are very, very often unprecise or completely off the road. Having a focus on it I couldn't nail the problem - five stairs at 16:30 are counted correctly, the same five stairs an hour later are not counted at all. I wonder why there's no possibility to correct them in the app or the web portal? In my opinion that would be better than getting mad about an automatism that doesn't work - or ignore a keyfigure cause it's unreliable.
There are lots of things that can affect the floor counting. One simple thing as changes in the air pressure or that you are skipping steps or holding in something can make the counting fail. 2 floors difference is extremely good.
