If it is failing, then it is because the lock is not set right, and because it has a steel lockbar interface. That's the downside to steel interfaces. They don't wear over time and your lock won't travel, but you lose the natural ability of titanium to gall, or "stick" to steel that keeps titanium lockbars from slipping on their own most of the time.
If the lock is set in the right place, then it usually isn't a problem, but with the recent trend of everyone wanting early lockup on their knives, most companies still try for that even though you really don't want an early engagement with a steel insert.
And I also have a Sebenza 25, and have had an SNG and XM-18, and have never had a problem with any of them.
I also regularly EDC a Shirogorov 95T, which has a steel insert, but much better overall geometry in the lock (though not particularly late lockup either), and have never had a problem with it either.
IDK, sometimes it doesn't etc... I just want to know I can trust a product.