What I have observed with electronic measuring tools is that when they render a different reading, its not always apparent. I have two electronic scales. The bathroom scale sometimes will give the same reading repeatedly, other times, the consecutive measurements of the same person give 3 different weights. OK, cheap bathroom scale. I replaced it with a beam scale that is always 100% repeatable.
I have a electronic postal scale (purchased from USPS on line) and it goes up to 10 lbs and weights to the 1/10 ounce. Often, when removing a package, it won't return to absolute zero. Reset it, weigh a couple of items, then again, won't return to zero.
Recently, after paying postage on line, get to the post office, their electronic scale shows I am 1/10 over and I had to pay for 1 more pound. If the scale would of told me that, I would of repackaged it or charge the customer more.
So now, I figure if I am anywhere close, assume the scale is to low and adjust accordingly to the next incremental postal weight and cost.
Now, with the beam scales, I get repeatability every time. To bad I don't have a beam scale for my shipping.
The less variables the better the work. If I start mixing my own, which is why a purchased the scales, I would like to follow a formula the best that I can. I think if I am making large quantities small errors may not show up, smaller quantities, the error may factor in.
All things being equal, I would rather have accuracy even if not needed rather than occasional having errors when I need it. I make enough errors on my own without needing any help from some digital device.