1% can be a lot …
Any edge you can get in a life-threatening situation is very welcome - even a 1% chance.
What if each choice or skill below gave you only an extra 1% chance of survival?
What if the model gun you pick gives you a 1% better chance?
The sighting system is 1% better.
The trigger is 1% better
The caliber is 1% larger.
The round’s penetration potential gives another 1%.
The round’s expansion potential +1%
The number of rounds available +1%
The way you carry gives you another 1%.
Your situational awareness +1%.
Your clarity of thinking +1%
Your thinking speed +1%
Your draw speed +1%.
Your shooting speed +1%
Your shooting accuracy +1%
Sure each item alone is not a big deal in and of itself (only 1%) but combined they make a significant difference. This short list alone gives you a total of 14% greater chance of surviving - and it's no where near a complete list.
Bottom line ...
Taken together, both slightly better equipment choices and minor skill improvements can increase the odds of survival significantly.