True story. A girl that we trained for only four weeks was in a parking lot one night. She was getting in her car when she felt a knife at her throat. She did a basic disarming technique that she had learned and turned the guy's blade upon his own kidney. As soon as he felt the knife pierce his skin he fled into the night, leaving the girl holding the knife with his blood on it. She got to keep the knife. Another true story. A seven year old held a kidnapper at bay with kung fu until authorizes arrived on the scene. The little girl became a hometown hero. Another true story. A sixty year old woman was getting into her car when a much bigger, younger man attacked her. She had trained for a few months in Tai Chi. She knocked him out and restrained him until the police picked him up. None of these women had black belts or brown belts or any belts. All they had was a serious commitment to retrain their reflexes and overcome their fears.
If you just take a course, it will not guarantee you become a fighter or that you will even survive. If a person wants you dead badly enough, they'll hide on top a building and take you out with a long range rifle or something, but if they just want to rape you or rob you, then chances are they are just thugs and are probably not trained. Still, a course that you take and then forget will do you no good. If you take a self-defense course, take it seriously, let it become an everyday part of your reflexes. Attackers expect their victims to be docile. They don't expect to attack a woman and have her leap onto him and smash his trachea with the palm of her hand or have her grab the insides of his legs where the flesh is tender and pinch the life out of him. They don't expect her to jab an ink pen in his eye socket or something like that. You don't have to be black belt for these things, but you do have to overcome fear and take advantage of every opening, closing the distance. At any cost, stay out of arm's length and if you can get in, go for the goods. Do the optimal amount of damage with the least amount of effort. A predator depends on his victim's fear, on her helplessness.