Here is an example of what your saying about Glock due to a worn leather holster.
http://www.itstactical.com/warcom/f...her-holsters-can-cause-accidental-discharges/
I'm a huge Glock fan they were all my wife and I carried pre kids. However we both carry condition 1 so we moved to colt defenders because the safety is identical to the full size 1911s.
Have seen that guy's photos before. It's a pretty old article. My initial reaction the first time I saw it remains the same today: That wasn't a proper holster for what he was using it for.
I'm in total agreement that I would want a secondary safety on a pistol carried in that garbage he's wearing.
Belt slide made from cheap leather is always going to collapse and not work properly very quickly. Good quality reinforced leather is not cheap. Leather/Kydex combos and straight Kydex for me, unless I'm just walking in the woods and have a new pistol I haven't gotten the proper holster for yet. (And the pistol would have to come out of it when transitioning to being seated.)
Maintaining your holster/gear and watching for wear and weakness in reinforcement is part of the process. Like many who've shot for a long time, I've got piles of the things.
(Even have a few still in wrappers that need some time spent with them to see if they really do what they're supposed to -- which is done with an unloaded or at least non-chambered pistol in them.)
I won't even give away the few belt slides I own. I'm too cheap to throw them out, but they don't get used unless it's just to take a walk in the woods with a pistol I haven't purchased a proper holster for, or it hasn't arrived yet... And I won't give them to anyone who doesn't know better than to only use them as a last resort.
There's lots to think about when choosing a holster or having one custom made by a proper leather holster maker.
My range allows holster draw after qualification by a range safety officer and they ban cross-draw, SOB, appendix, inside the waistband, and shoulder rigs completely. The RSO retains the right to tell you "no" for a cheap collapsing leather OWB also.
They prefer a Kydex or Kydex/leather combo, OWB, strong side only, and will give any cheap leather the hairy eyeball it deserves.
Here's another point many non-shooters may not realize but should be said in any discussion about holsters and bad ones. There's damn near zero reason to ever unholster a firearm. Reholstering also therefore is wholly unnecessary.
(If you drew it to shoot, just leave it out and put it down after the cops arrive or probably before, if you don't want to get shot yourself. Reholster when the adrenaline and shock wears down or remove the holster and reholster it in a safe direction OFF body.)
I've had a particular series of habits now for a long time and they include simply leaving loaded firearms in their holsters. Remove the whole rig and lock it up properly as a unit.
Most NDs happen when you're screwing around with the pistol unloading it or loading it. Why do it at all? Pop your belt loose and remove or drop trou and remove as a unit.
You can't fire the thing if you can't get your booger hook into the trigger guard. In a good holster, it's not ever going to "go off" even if you drop the entire rig from belt height onto a hard floor. (Exception here, would be a very old revolver without a transfer bar -- say cowboy action stuff, and that's handled by never loading a round under the hammer, ever.)
Unholstering and manipulating the pistol daily, especially at bedtime when the sandman is calling, is a very bad habit to get into, IMHO. YMMV.
The less you jack with it, the less accidents and negligence can occur.
Obviously there's also the topic of proper security of the holster and pistol unit when not on your body, but that's a completely different topic altogether.
There's also quite a bit to be said for having a specific safe place to administratively unload firearms at home, for things like maintenance and cleaning, at specific awake and alert and focused times, and again IMHO, standing next to your bed at night is not the place to be doing that.
Anyway. Mr. Collapsed Cheap Leather's self-induced problems will not be being repeated at my house or on my belt. One does have to think very seriously about holsters and not just buy the $35 garbage on Amazon.
Ask an LE friend sometime to try to collapse one of their duty belt holsters, even in leather. I bet you won't find many that will collapse much, even squeezing with both hands. You also won't find many (if any) that don't have some form of pistol retention beyond simple friction.
Right now I'm pretty impressed with the offerings from CompTac for my uses. SHTF Gear are also adequate but not as well built. I'm intrigued by the N8 Tacticals but haven't tried one. Have a couple of Italian made leather holsters that are so tight you can hear the metal fart when inserting the pistol and they actually need some work to soften them up, without overdoing it, and they'll have to be monitored for condition. They all do, of course, but I worry less about the Kydex and Kydex/Leather combos than the leather only.
I'm a bit too cheap to have custom leather work done but considering it for the big Sigs. Dropping over $100 on custom leather and usually closer to $200 isn't happening unless the pistol is a favorite that will never ever be sold.