It is to get accurate timings with all those minutes, seconds and micro seconds. So that they will be able to select the winners with no doubt.Hope it helps and pls mark as the best answer. :-)
ya right.i too had this in my mind
This is because a stop watch can accurately display the amount of time taken by any player to complete a task. In case of other watches, it is necessary for a person to keep track of the time, whereas in a stopwatch, only a button needs to be pressed and the time taken will be recorded.
Hope this helped!