You might ask, if I don't care about the scale accuracy and results, why do I even need the make the measurement?
In any case, after the weigh scale is calibrated, and before its next calibration, you can use a single mass, which is also calibrated, as a check standard during the time interval between calibrations. Use an appropriate SPC method to demonstrate no shift in sensitivity, which will give you confidence in weight measurements.
Some labs use one before every measurement, some at the first of every shift, some longer.
The greater the scale range, the heavier the mass needs to be--can't be putting 5 lbs. on a 100 lb. scale to check sensitivity.