They stick onto the end of a power screwdriver better than a Phillips head screw. It was an assembly line speed thing. Torx was used for the same reason, but they were used with robotic assembly tooling.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!