Not all flashing lights have the countdowns. Some seem to turn quickly after a few flashes to a yellow, some seem to go on forever. Some yellows are VERY short and some long, Some intersections have a distinctive few seconds between when one set of lights turn red before the others turn green, others have no wait. I prefer the ones with the red/green delay. Definitely reduces possibility of late runners and oncoming traffic already in motion during adverse road conditions.