I give Glock his due for inventing a better mousetrap and marketing it well. His marketing strategy is brilliant. For example, he is able to convince a lot of the gun world that this silly doohickey in the trigger makes the Glock safe. He also created a simple to use and reliable gun that is cheap to make.
But unless Glock changes, his downfall will be the refusal to advance his design (true for a lot of brilliant inventors -- for example, the old Wordstar program). There are now better Glocks out there, including the Steyr M9 and maybe the HS200. Glock's rigidity is stopping him from making his guns into more ergonomic weapons that work for more people. It may also be his arrogance that stops him from incorporating better safety devices like a manual external safety, a loaded chamber indicator, and an integrated key lock. Right now, Glock holds onto market share not because he has a better product, but because the public perceives it to be better. That will change unless Glock becomes more innovative and moves into the next generation of pistol development. Sure Glocks are reliable, but so are a lot of other guns. The more innovations that appear in the marketplace, the more the Glock looks like a dinosaur. Unlike the 1911 dinosaur, the Glock lacks the beauty, ergonomics and history to have a long-term loyal following.