My guess is that the numbers that manufacturers give for these are mean-time-between-failures, meaning that some will last longer, and others less long. In the days of film, 100,000 exposures involved some serious coin in film and processing costs. Most amateurs would never get there with a single camera, particularly those tyros splitting their time among cameras or systems. These days pressing the shutter button is perceived as "free" -- my guess is that many more folks will get to 50K exposures with their favorite digital cameras than did on old-style Ms in the film days.
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