Some of the kabooms reported as being due to Glock's design were confirmed as being due to problems with the ammo. The early Federal .40 rounds had issues, and the Portland Glocks that blew were determined to by White Labs to have gone up due to overcharged ammo. As for maintenance, the problem tends to be oiling the striker channel and/or failing to clean it. Both will cause issues.
Yes, except like all things, 'Glock' those batches of over-pressure Federal 45 acp ammo don't tell the whole story; and, by Glock's own subsequent admission, there was a lot more involved in the PPB kaBoom! events than just that Federal ammo. The old #4256 trigger bars were also - and, perhaps, most culpably - involved.
I've, probably, read every Glock kaBoom! thread ever written. I've studied all the theories, and probable causes. I think Glock, Austria, knows the correct answer, too, but isn't going to be anymore forthcoming now than in the past.
Would you like my personal opinion?
I believe that in addition to all of Glock's other well-known shortcomings; i.e.: larger chambers, heavy chamber rebate, negative frame harmonics, excessive polymer flex, plastic guide rods, defective rails, and that run of defective 45 acp barrels the factory sent out a few years ago something else is taking place.
Still want my opinion?
In particular regard to Glock pistols above 9mm chambering, I think Glock's weak, 'Modified Browning Lockup' occasionally opens up too soon; and, THIS is the principal leading cause of Glock's mysterious kaBoom! problems.
(Feel free to disagree; but, I strongly suspect that I'm correct. Oh yeah, I also carry a Glock Model G-21, everyday, and have been a frequent contributor on Glock Talk with a total post count of well over 8,000 posts during the past 5 years. However, it should be obvious that I ain't no Kool-Aid drinker!)