Ive been riding all sorts if 2 wheeled machines for the best part of almost 2 decades, MTB mostly, even these days i'm still having offs of some description every other ride, the difference is longer you've been doing it the better you are at going with the crash to mitigate potential injuries, but even then some crashes happen so fast and unexpectedly you just cant prepare for that, and injuries are bound to happen.
over the last couple of years i've had a few really bad ones, that have required long recovery times, mostly ligament damage. but thats the beauty of the human body it heals, albeit slower as you get older...
Crashes are an inevitable part of riding, that's not to say it will happen often but you can be almost guaranteed that it'll happen at some point, no use in fearing it, how often all depends on the situations you put yourself in.