Zach Baker describes how the claw crane arcade games actually work.
Basically, most crane games are designed so the claw is randomly (and only once in many games) strong enough to let players win. Some even weaken in strength after a short time so players get close to victory only to see it slip from their grasp! Since the manuals for many skill games are available online, this is not hard to verify.
I never won anything from one of those games. Then again, I didn’t play them often because they always seemed rigged.