Why can't a scale weigh?

You can buy a VHS player for $25. Open it up and marvel at the sophistication. Load a tape, watch it do its dance, "M-load" the tape, and then play back perfectly (assuming you can find a VHS tape, of course). I am amazed it does it at all, much less for $25. The tolerances involved in playing that tape are measured in the nanometers, and it does it perfectly every time. When was the last time you had to adjust a VHS player?

Now step on your $25 bathroom scale. If it's made by Healthometer, chances are that it will get your weight wrong by at least a few pounds. Check out the Healthometer reviews at amazon. "Zeroing out the scale and stepping on it, it weighs heavy by nine pounds."

With modern technology, how hard is it to make a bathroom scale that weighs accurately? "Don't set it to zero. Six is zero," my father told me. I didn't shoot back, why don't you buy a scale that does what a scale is supposed to do? (After all, it's likely that the error is a proportion of the weight, not a bias, so "six is zero" works only for a small weight range.)

I have tried three Healthometer scales, and none of them weighs accurately. Does anybody have experience with one that does? (Before you answer "yes," please confirm that your scale really is accurate.

Maybe a class action lawsuit would fix this issue.