This has always struck me as something of an outdated sentiment...
It would seem to me that in the modern era of CNC Machining, firearms typically run perfectly right out of the box, and typically a single box of ammo (50 rounds) is more than enough to inspire confidence, as generally speaking, if a semiautomatic pistol can get through a magazine or two without malfunctioning, then you can be fairly certain that it's good enough to trust your life to, because realistically speaking, that's as much ammo as you'd use in a real self-defense situation.
Break-in periods are a thing of the past, a relic from an age in which firearms were largely machined by hand, and although they generally had very high standards of quality, firearms were more tightly fit, providing very little clearance between moving parts which in turn made them less reliable because all it took was a bit too much lint in the nooks and crannies to impede function.
Nowadays, firearms aren't very tightly fit at all, which some folks view as a negative, yet their outstandingly reliable. Take a Glock for instance, if you hold it up to the light, you can see that there's a considerable gap between the slide and frame, yet Glocks are known to be of the utmost reliability.
That being said, if you're looking for an excuse to spend an afternoon at the range, then more power to you!
