Scope failures can be very aggravating, particularly the scopes that suffer a slow death. A guy can burn a lot of time trying to figure out why a rifle is acting up when a rifle scope begins to fail internally. Of course it's most aggravating when a sick scope causes a poor hit on a game animal.
If I have a scope fail, I'd like it to completely fall apart instantly, making the diagnosis very straightforward. The scope failures that have caused me the most aggravation are the slow but steady scope deaths, where the shifting reticle/lens begins to cause surprising and unexplainable changes in POIs, and the adjustment turrets become inconsistent and unreliable. 3-shot groups from a proven load that grow in size over time have been the harbingers of a failed scope for me with two different scopes.
A progressively failing rifle scope can cause a guy to hate life. The repair/replacement warranty will not mean near as much after a bad scope caused an unexpected shift in POI and a poorly hit animal.
I can usually recognize the hunters who have experienced the aggravation of failing rifle scopes. They're the ones that place more value on purchasing a scope with a low failure rate in the first place, rather than purchasing a scope primarily due to an outstanding reputation for warranty repair/replacement work.
