Luck is a cool thing but if you have it turned on while you use the Grid for basic stuff, it goes off a bunch and you can easily burn a bunch of luck points that way. The same goes for driving, though I suspect when it pings there it's probably still doing you some good somehow.
If it could be auto-activated in combat via a setting or if basic seemingly unfailable stuff like checking your gridmail could not burn luck, that'd be neat.