Why is usually that important? If a unidirectional bezel is knocked and accidentally moved with a dive, it may only Exhibit an extended underwater time. Meaning the wearer will overestimate in lieu of underestimate immersion time, and in scenarios that have to have decompression stops, this can be a make-it-or-break-it https://www.watchesworld.com/frozen-in-time-luxury-watches-for-winter/