Why is the fact critical? If a unidirectional bezel is knocked and unintentionally moved on the dive, it can only Screen an extended underwater time. Which means the wearer will overestimate rather than underestimate immersion time, and in circumstances that call for decompression stops, This may be a make-it-or-crack-it element https://www.watchesworld.com/frozen-in-time-luxury-watches-for-winter/