I believe only shots with an assignable cause, such as trigger jerk, wrong pellet type, gnat in eye, or earth moved during trigger break ….are truly “Fliers”.
Few shooters realize the true capability of their rig cacpability, sice they mostly shoot groups with only a few shots. If one shoots over a hundred shots with the same aimpoint and conditions, they typically see a much larger group that more accurately reveals the REAL capability the the shooting process that includes, gun, pellets, and shooter capabilty.
The large number group will likely contain many shots that would have been called fliers that are really p[art of the normal distribution under those conditions. Of course changing the process, as by cleaning the barrel, using a different pellet type etc might give better results, but its a different process, right?
LD