It's up to the SITUATION.
The same three rules apply, APPLICATION, APPLICATION, APPLICATION.
I'm not in Baghdad, I'm not on the gun range, I normally do not carry with a round in the chamber or under the hammer.
With semi-autos I drill with charging the chamber, and I use dummy rounds in the mags so my clear & charge is fast & smooth. Having been in combat with issued M9 & Checkmate magazines, I'm perfectly aware that sidearms don't always function...
Failure drills are a must if you actually think you will get into a gunfight.
I'm the freak in this bunch, when I carry, most times it's a 'Cowboy' revolver with the firing pin on the hammer, and I'm working. With fixed firing pin, you are an idiot to have it over a loaded round...
I don't want snake shot in my leg when a tool strikes the hammer.
I've been near or present when 'Accidental Discharge' happened,
I was present when the firearms instructor from the Kentucky state police shot himself in the leg on the range demonstrating 'Quick Draw', I was present with the armorer for a city police department shot his finger clearing a jam, etc.
This spring, three people I know shot themselves, one in the butt (holstering loaded), one in the hand (charging the chamber) and one in the leg (drawing) and this is just this spring!
One I didn't know shot himself in the knee, don't know the details.
This is in my little, low population town...
Two of the three I know the details were 'Firearms Instructors' in one capacity or another, one park service and one teaches NRA Hunter safety classes. The park service guy is still sitting on a 'Donut'!
I'm old legs don't work as well as they did, but I have no wish to shoot them up, and if I shot myself in the butt I couldn't sit down and waste time on this forum!
If I lived in Chicago it might be different.
In 40+ years of POTENTIAL sidearm carry, 98% of civilian life I don't carry, only two times in 40+ years I felt the need to draw on a human in civilian life, and once I wish I'd been carrying & wasn't (my wife was!).
It's up to you & how you practice, and if you don't practice, you probably shouldn't be carrying...