What is wrong with these scales?

Some scales are better than others...I have had electronic scales that cannot get a true accurate result and you can see the scale hovering unsurely between two amounts before picking the closest weight either up or down to the nearest pound/kilo. My new electronic scales are super accurate and i only paid $20 for it..a brand called beurer...it is just a scale only..none of that water/body fat/muscle % included...they never seems to be accurate with all thoses extras i find...it could just be the brands i bought though lol. Check with the instructions first if there are any weight variations to the nearest pound/kilo. Otherwise take it back and buy a new one.