Why is that significant? If a unidirectional bezel is knocked and accidentally moved with a dive, it can only Exhibit an extended underwater time. Which means the wearer will overestimate rather then undervalue immersion time, As well as in conditions that require decompression stops, This may be a make-it-or-split-it element https://www.watchesworld.com/frozen-in-time-luxury-watches-for-winter/