In this video, Rory Miller makes the case that the problem is not with the locks themselves, but with our teaching methods.
A principles-based approach allows relative beginners to improvise joint locks with one hour of training, something that many traditional approaches have failed to do with hundreds of hours.
Joint locks are NOT primary self-defense techniques.
If you are in a position that requires self-defense you are justified in and likely need a higher level of force.
However, if your job requires controlling violent people with minimal injury you must be good at joint locks and you must be able to improvise them under pressure.
Ball and Socket Joints
Lock Flow Drill