I remember reading a long time ago about carbon fiber wheels, and how they benefited over aluminum wheels because they were designed to handle the flexing that inevitably happens when hitting obstacles. In particular they referred to the curbing on racetrack corners which is purposely bumpy to discourage drivers not to hit it and cut corners.
According to that article, the constant bending and flexing of aluminum wheels eventually causes fatigue cracking (or just bends). Carbon wheels can apparently handle much more severe flexing without fear from fatigue cracking.
This is going back a LONG time, so I'm definitely not pretending to be knowledgeable on the topic, and I'm sure carbon fibre wheels (and maybe wheels in general) have evolved by orders of magnitude since then.
What I do know is, everything bends when a force is applied to it. What I don't know is whether a wheel moves by millimetres, or tenths of a mm, when it hits something. That's a question for the experts.
