Things that make you say...Hmmmm

I decided to keep track of my weight loss using Wii Fit, but now I'm not so sure. I haven't used the thing in so long it said it had been 280 something days. I put fresh batteries in the Wii board and remotes. Here's the thing...It said I was down 10 lbs more than what my regular scale says. I wish I could say that the truth. I don't know. Which one should I go by?