I weigh once a day and I don't usually worry about the small fluctuations...but lately I having a difficult time getting a good reading. I'll weigh three times and get three different numbers (and I try to step on carefully, in the same spot, etc.). The scale is on a hard floor, so I can only think it isn't very good. It's very frustrating when I weigh myself three times and the numbers vary by as much as five pounds! Scales are evil I tell you.