Seems to me it's more like bad refereeing / bad math.
The shot clock starts at 24. When the 1st second passes, it goes to 23, 2nd second passes = 22, 3rd = 21, 4th = 20, 5th = 19, 6th = 18, 7th = 17, 8th = 16.
So, eight seconds have passed at the exact moment that the shot clock turns to 16...