My wife has a fitbit. About a year ago, she told me how many steps she had done for the day. I said "honey that's impossible." She insisted that she is on her feet all day and constantly moving. I said, "I understand but you can't possibly have taken that many steps." She insisted it was correct.
I did the math. Divided the steps by the minutes she'd been awake that day. Long story short, the thing must have thought she ran to work (17 miles) and home. The amount of steps PER MINUTE AWAKE was over 120. When I said "that means that from the time you woke up this morning until you got home from work, you were running the whole time at a two steps per second pace."
She got so mad she didn't wear it for a couple months.