Luck is a limiting factor, which must be tamed by proper engineering. If left unchecked, and your creations are working by Luck alone, you have to worry about what will happen when Luck runs out to get a gallon of milk.
Luck is also fickle. If she catches you depending on her, she’ll back out and leave your gadget high and dry.
Worse, if she catches you flirting with Chance, you won’t know what hit you.
So avoid depending on Luck. Sit back and enjoy a proper cup of luke-warm tea.
And turn on that infinite improbability drive. If you dare!