I've recently learned that there is an official Kilogram (IPK) kept in Paris which is used to calibrate, directly or indirectly, all weight measurement tools. I've also learned that each time the IPK is measured, there is a good chance the measurement is a little different by a few micrograms. Statistically speaking, this is a chance error being observed in the measurement.
Now for my question, if you take out any human component, is the reason for the chance error in the measurements due to the probabilities at the quantum level? Can quantum probabilities observed while weighing micrograms?