I know far too many casual shooters who blame their sights for their shot deviation. Once user error has been ruled out, adjusting or changing your sights may be an option. Granted, changing your sights is always an option if your firearm has that feature.
Here’s a great reference blog post about sights.
https://www.usconcealedcarry.com/blog/draw-bead-know-pistol-sights/
@Dawn Of course I have 
Replaced my Officer’s Model factory no dot sights with a Millet MKII that over hangs the rear of the slide giving me 7/8" more sight radius and a matching front dot sight about 29 years ago. Beat out the old ones from the correct side (they only come out and go in one way) and beat in the new ones. Fired/adjusted/fired/adjusted and was eventually able to hit a 2 liter bottle at 100 yds repeatedly. They are zero at 7 yards and 100 yards and I’m a bit high at 25 & 50 yards using military match TZZ 230gr ball.
Cheers,
Craig6
Yes, on my Ruger GP100. I changed the ramp sight, to a Hi-Viz fiber optic. With the green light pipe, I did better. The big difference, was the red. It made that gun, in my hand, a viable 100 yard shooter, on a full size target. Hitting any target, especially a steel one, at 100 yards, with an open sight handgun is so satisfying. Since I hunt with this revolver, it gives me the confidence to take a shot at a white tail, at distances the .357 is effective for that purpose.
Changed from stock Glock sights to XS F8 night sights. My first shot from the draw got much more consistent along with my groups. I’ve since shot a stock Glock and found the sights to be to “busy” for me. The sights I’m using draw my attention towards where it should be on the front sight.