Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Works inconsistently!

The motion detector on this system is not very good. Even if my cats spend a fairly long time in the tray doing their business, the motion detector only trips the scooper sometimes (the light blinks while they're in the tray, indicating that the motion sensor knows they are there, but once they've gone it's supposed to keep blinking until the poop has dried and it auto-scoops. Instead it stops blinking when the cats leave the tray and it never scoops). It has gone for days not detecting the cats, then might work once. In the meantime, the tray has gotten full of poop. When it does work, it's pretty good, but after 2 weeks (with 2 cats) it stinks! And I've had to scoop out the poop at least every 4th day to keep it from getting overly full (it has a very small 'reservoir' for the old poop).I'm not impressed. I don't have to scoop every day, but I do have to push the button myself to make it work, so it isn't useful for the long weekends away I'd hoped it would be great for.