Lumpy, if you’ve reached a plateau and can’t seem to get better, it might be worthwhile to find an NRA pistol course (or something similar) in the vicinity. Sometimes a 2nd party (that’s not just some bubba at the range) looking over your shoulder can make a huge difference.
Because sometime practice just reinforces bad habits. It’s happened to me more times than I can count… Well, no. More times than I can remember.
Or maybe you’re just expecting too much from yourself. I’ve been shooting handgun for 20 years and still have bad days when I can’t hardly hit the target (just pack up and go home rather than practice bad technique), and I have guns that I can’t shoot so good. I’m pretty sure every gun I own can outshoot me so I try not to blame the hardware, but some of them just don’t fit me - I can’t shoot S&W revolvers worth a damn, for instance.
I’ve never missed anything I’ve shot at. That’s good enough for me.
Not very good, I need more practice. Somebody want to buy me a case of 9mm?
With my Beretta 92 FS I can consistently shoot a 3" group out to 25 yards. That goes up to about 4" with my S&W 66.
If I’m shooting for time, add an inch or so to each of the above groups.
I’d really like to have a 9mm if anyone was feeling extra generous. I ditched mine in favor of the .45, but .45 is just too damned expensive to put as much lead down range as I’d like.
That’s why I have a 9mm, but I do keep it loaded with hollow points. 
If I am lucky my assailant will, in fact, be as large as the side of a barn.
I’m trying to get better.
… the flat-bellied, buff, 6-pack guys being ‘keepers’? 
My accuracy seems very inversely proportional to caliber. With a Ruger Mark II .22 I can do amazing shooting. With my Ruger 9mm…not so well. My Ruger Super Redhawk does better with me, but that’s mainly because it has the 9.5-inch barrel, I think.
My concealed carry handgun is a Glock 26, and I’m not nearly as accurate as I would like to be.
I used to be Deadeye Doris with my old .22 rifle though. It used to infuriate friends I went shooting with (mostly boys) when I could do things like line up empty .22 casings on a fence and knock them off one at a time from about 30 feet away. With my .22 rifle, it pretty much was “if I can see it, I can hit it”, and the biggest limits I had were iron sights and poor eyesight.