When the devices cost ten bucks. As a rule, the cheaper the devices, the less accurate they are. It's my experience that most domestic bathroom devices are inaccurate - usually on the light aspect. , I've listened to those complaining about how 'heavy' the devices are at my gym. Sadly Keto Ultra for those clients, the devices are very accurate. . When it's pm and you've absorbed a cow for lunch. Under frequent conditions, we're all heavier at the end of the day. Not fatter, heavier. Natural variability indicates that somebody like me can simply think about - pounds (.-.lbs) more in the night.