To deal with any inconsistencies in the speed at which they complete the 58.5 seconds. If a particular defective clock takes 59.9 seconds instead of 58.5 it'll

To deal with any inconsistencies in the speed at which they complete the 58.5 seconds. If a particular defective clock takes 59.9 seconds instead of 58.5 it'll be just fine, as it will start going again when it gets the next minute pulse from the central system.