The safety is very easy to switch to fire unintentially and they can fire unexpectedly. No exposed hammer , awkward handling and generally not user friendly. The fellow I knew who shot himself was an experienced Marine Infantry man and if he had an accident imagine a newbe! There were many reasons why the 1911 won the Army`s handgun competition over the Luger and safety was a major one.
Even the Germans gave up on the Luger and went with the P-38 as a replacement and it is a totally deferent design which is much safer for the user.
I like Lugers, but would never rely on one, give me a 1911 or P-38 any day, that is if I can't have one of my beloved revolvers.