Didn't you figure that a lot of people cares about having a measure that a conductivity is known to be less than 0.001 [unit] with a specific probability? As I said, you don't always measure to get value digits, but to get a bounds. The difference between 0.01 and 0.001 is a factor 10, so if you have a thermos with ten times better isolation, your coffee will keep warn way longer.

In your case, it seems like you worry about the number of zero after the decimal point. But to make them meaningful, you have to specify a physical unit. Think about the number of zeros you have after the decimal point when you play with pF capacitors together with your processor crystal. But 9pF instead of 10pF is still a significant change in value. If you step down to a DRAM memory, you may think pF is huge when the intended capacitance may be femto- or atto- instead of pico-farad. atto is 1E-18.