We have a unique opportunity: We own a very large number of lenses and cameras subjected to rather harsh conditions. Basically, we have a laboratory set up to stress test photography equipment and we share those results with you.
Our numbers reflect heavy and hard use. Your personal equipment shouldn’t fail nearly as often; it isn’t subjected to rental conditions. But this does provide some comparison about how fragile various pieces of equipment are.
It’s not completely scientific, but with data on over 12,000 copies resulting in over 2,000 repairs it’s a bit more useful than posts on a forum going back and forth between “mine’s great” and “mine sucked.”
This list is not a comment about how good a lens is. It’s simply data about how often it breaks under harsh conditions. Some of my favorite lenses and cameras are rather fragile.

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Other conclusions I think are valid:
- Every manufacturer has some great lenses and some weak lenses.
- 70-200 f/2.8 lenses are likely to fail no matter who makes them. We think of them as ‘built like tanks’ because they have that heavy, all-metal case. That case, though, is as packed with mechanics and electronics as anything you’ve ever seen. There’s a LOT of stuff in there that has to work perfectly. Inevitably, some of that stuff breaks.
- Sigma’s big zooms still have trouble with their HSM motors and OS units, but Sigma really does seem to be doing better. Their large zoom lenses are still on the list but the frequency is lower than it used to be, in a year when my new accounting system made most numbers look worse. Sigma’s prime lenses and smaller zooms have excellent repair rates.
http://www.lensrentals.com/blog/2013/08/lensrentals-repair-data-2012-2013