I have a special set of circumstances (a disability) that would prevent me from fleeing from a potential bad person.
So, the numero uno concern for me is RELIABILITY.
I carry what I know, through trial and error, to be the most reliable firearm and ammo combo for me.
Which in summer is a Glock 27 in .40, and in the one month of winter (south Ga) a Commander in .45.
Both are stacked with Cor-Bon 200 gr. JHP because it has proven over many years to be accurate, potent enough for the job, and most of all reliable (in my guns).
I guess the bottom line is I choose RELIABILITY first and LIABILITY second.
Test, Train, Test, and Train some more.
No one WANTS to shoot another human being, but if forced into it, be prepared.