A lot of interesting discussion here. I'm sure this is a Murphy's Law thing but from my observation of my own handgun collection I've noted:

A gun's sensitivity to spring condition is inversely proportional to the size of the gun and the weight of the ammo.

For example my Beretta collection is not at all sensitive to spring fatigue but my Kahr PM9 demands a regular spring tune up every 1500 rounds. I had an XD45 once that would go through magazine springs every thousand rounds. I attributed this to the workout the mag gets moving 13 rounds of .45 ACP. If I didn't replace the spring I would get frequent return to battery failures not related to the recoil spring.

I also tend to use a lot of extra power recoil springs from the spring guru (Wolff Springs) and that tends to require a corresponding change in my magazine springs. My CZ75B in .40S&W was a classic example of one spring change leading to the other. The extra power recoil spring was needed to over come some feeding issues, and that led me to an extra power magazine spring. I don't really know whether or not there was a legitimate technical reason for requiring this dual spring replacement but the gun behaved as though there was.

This thread hopefully points to the fact that guns are indeed mechanical things that need periodic maintenance and springs are effectively time change items like oil filters and air cleaners...LOL.