The definiton of second is the time needed for a cesium-133 atom to perform 9,192,631,770 complete oscillations. Why 9,192,631,770 complete oscillations? Is that because it is the interval of 1 sec that is about the same as the old definition? And the cesium clock, is claimed to accurate to a single second over 3 million years. Therefore, couldnt we just take this error into account, so that there will be no error?