But Apple's right (here I go again). The movie had to continue, so Michael avoids the hit.
That's obviously the main reason. I real life, Michael probably would have been dead or severly wounded.
But it isn't unplausible to think that the shooters were hiding from a distance. It's not like they could just stand there and wait for Michael to appear without getting seen by the intense surveillance of the compound.
"It was between the brothers Kay -- I had nothing to do with it."