Barring ammo issues, 99% of Glock 9mm failure to feeds is a lose grip, or a limp wrist, and no I'm not guessing, and I didn't read that somewhere, and the 17 was the worst.
When the Glock pistols started hitting the police and sheriffs' offices in my area, I was responsible for training the officers, both street, and tactical.
With a firm grip, and a stiff wrist, they are as reliable as it gets. And yes, I'm also a Glock armorer.
They're far from the most accurate, but they're accurate enough for fightin, and their their forte is, they'll feed just about anything.