This:
bulletslap wrote:The original Glock Magazines were not "drop free", this slight protruding of the magazine probably allowed for a more secure grip in order to pull the magazine out, and continued as a vestige of this practice.
Maybe even this too:
AJSully421 wrote:It also helps if the mag is all muddy that you can insert it and there will be a small area for debris to sit without causing a problem.
The G17 was designed for the Austrian military, and they clearly had a different philosophy about magazine change procedures. I bought a G17 in about 1993 or so, and all the mags stayed in the gun until pulled out. Made my mag changes a little slower in shooting courses, but then I had lot more bullets than everyone else so didn't have to change as often.