From personal experience over a few decades and literally tons of rounds of all sorts and calibers, I really have a hard time believing people when they say they've NEVER had a stoppage or problem, and thats with ANY gun. And that just becomes more of a problem as the round counts increase. Im thinking that they are probably just misremembering.
If you shoot enough, regardless of what the gun is, or the ammo is, sooner or later, you WILL have a stoppage or failure of some type.
Stoppages arent always ammo related either. We can cause them to happen, the gun can cause them to happen, all manner of silly and stupid things can cause them to happen.
Yes, maintaining your guns is a mandatory thing to do, at least to me it is. And Im always amazed at the number of people who claim they never clean and maintain their guns and still NEVER have any problems. Yea, OK.
Yes, good factory ammo is a good idea, if you can afford it. I dont know many who shoot a lot, that only use factory ammo, unless they are being sponsored by someone or just have a lot of money. From what Ive seen, "most" people really dont shoot all that much and "a lot" here is perception. 500 rounds a month vs 500 rounds a week is a bit of a difference. How many actually shoot 500 rounds a month every month?
Most people I know who shoot a lot, are shooting reloads or commercially remanufactured ammo.
Most of that ammo is usually pretty decent too, but with reloads, the more the brass is reloaded, the more likely you will have some sort of failure, as the brass starts to wear. Personally, I look at that as a plus, as it lets you practice more realistic stoppage drills, as they happen randomly, and without warning.
Dead primers are a fairly common cause of failure too, and probably the most common Ive seen with new factory ammo.
Improperly seated bullets is another fairly common problem Ive seen with factory and reloaded ammo that can also tie up a gun, and sometimes to the point that youre DRT because of it. They can lock the gun up tight and you cant even do a TRB.
Stoppages are just part of shooting too, and something that should be practiced regularly, even if you have to set them up. When one happens, you should just clear it without thinking about it and move on.
The last thing you want to do when it does happen is what you often see when someone who has one, they stand there with a stupid look on their face, looking at their dead gun wondering why its not working.