I had to stop my partners big gut shot cow last year since she had covered 200 yards & was almost at the ranch fence. He had knocked his scope mounts loose & off zero the day before & would have lost her. He kept shooting and missing and she would certainly have left public & started a painful process of getting permission & a long tracking job with no snow.
Some years ago, I took a bad fall on loose shale and dinged up my scope. I shot it a couple times and it was right on so I didn't worry about it. Turned out that something broke inside and the x-hairs would move whenever they felt like it. A couple weeks later, I shot a cow from about 200 yds. Even from a rest, I got a bad hit that I credited to user error at the time. When I got to her, she was lying down but head up. I was only 10 yds away and had a rest but it took 4 shots to hit her neck. I found out later that the x-hairs had moved and it was way off.
