I guess most meters have a display accurracy of 1 mg/dL, but that's just on display. If you check your blood twice in a row, you're likely to get at least a 5 mg/dL difference. I'm not even sure this is your meter's problem, but rather your blood having not 0.01 mg/dL-consistent sugar across all of your body.

Nevertheless 10 mg/dL is just the right accuracy needed to control type I diabetes. I don't tend to attach much importance to the last digit anyway.