Why is always that important? If a unidirectional bezel is knocked and accidentally moved on the dive, it may only Screen a longer underwater time. Meaning the wearer will overestimate as an alternative to undervalue immersion time, and in circumstances that demand decompression stops, this can be a make-it-or-crack-it variable https://www.watchesworld.com/frozen-in-time-luxury-watches-for-winter/