I measure some quantity with an instrument that it is precise to two decimal points. So maybe I get 8.84 V. Then I do some changes in my parameters and get 0.01 V. The two measured values are precise to two decimal points. But the first one has three significant figures, while the second one has only one significant figure. Why is that? Should not both of them have the same number of significant figures? Why are the leading zeros not considered significant?