Also you have to take into account disparity of force as in age / size of the attacker versus the target.
I carry a 6oo lumen tactical light, 4 oz pepper, a collapsible airweight baton, folder and a .38 titanium snub. If it comes to the point I need to administer some lead I will put one in their eye and one in their ear to make sure their brains are scrambled. Shooting someone to wound them only leaves them alive for another day to track you and your family down.
Luckily for me and them I am pretty good at avoiding conflicts.
The UK has terrible self defense laws. Glad I don't live there. You cant even have pepper spray.