Back in January of 1966, my Basic Training at Fort Leonard Wood was in a company made up primarily of Reservists and National Guard members. I think there might have been five of us that were Regular Army.
When at the range, the cadre tended to try to speed things up. When we were shooting 25 meters to zero, the sergeant looked at the pattern on my target and quickly adjusted the sights on my M-14 and then sent me back. Later in shooting at the range, especially so with pop-up targets, I wasn't hitting good at all. They knew I grew up with rifles, so they were confused. They had one of the sergeants take me back to the 25 meter range and shoot again.
Come to find out, when trying to zero, I was missing the target altogether, and the guy next to me was hitting my target instead of his. I had been zeroed based on his shooting. The new trip got me zeroed and I was good to go from there.
LOL! We had something similar while putting on a Women on Target program at our range. One of the ladies was told she would be shooting at target #6. After multiple courses of fire with a rifle that had been zero'd by a shooter, there were no hits on her target.
Owner of the rifle took the same gun and put a clover leaf group on the target.
Lady took over again and with additional coaching, still could not hit the target on #6. Range safety officer went down to the target and saw groups on the #6 sign over the target. When the RSO told her to shoot at the target at #6 she took literally to shoot at the #6 sign that was 2' above the target. She was following instructions! lol.