Tasers tend to have problems with clothing and distance, CS is easy to deal with if the person is trained, and bean bags are ineffective against large targets.

Tasers tend to have problems with clothing and distance, CS is easy to deal with if the person is trained, and bean bags are ineffective against large targets. Non-lethal force is useful in cases where the police have no reason to believe the other person is armed. It works sometimes but often it doesn't. Police and military are even trained to resist non-lethal chemical attacks like CS gas very successfully. When a person is armed with contact weapon like a knife or club, non-lethal is usually only used when a lethal option is in place.