In a self defense scenario, it's live or die. You or the bad guy.
Who usually wins a competition? The one who's most skilled? Ie: The one who has practiced the most? So if you're going to save your own life, and the lives of your family or friends in such a situation, shouldnt you have trained?
Bad news: The criminals are training more than you.
From a FBI study:
“The first thing that the researchers learned is that our assumptions about criminals not training are wrong". Nearly 40% of the criminal attackers in this study had received FORMAL firearms training. More than 80% of the criminal attackers regularly practiced with their firearms, with an average number of 23 Practice Sessions Per Year!
"They conducted these practice sessions in trash dumps, wooded areas, back yards and “street corners in known drug trafficking areas”. What that means is that the practice sessions were taking place in realistic environments, under conditions similar to those the attackers were likely to face in combat."
How many of you shoot your weapons 23 times a year in a realistic environment? I don’t know many people other than hobbyist shooters who do that.
The first thing that you could do is to increase the frequency of your practice sessions. Shorter, more frequent practice sessions are more effective than long sessions that are spaced months apart. Even if you don’t have regular access to a firing range, you can still practice drawing your gun and dry firing. There have been several research studies that have shown dry firing to be just as valuable as real shooting for maintaining marksmanship abilities.