Because he always gets his martini shaken, not stirred.
Shaken. Not stirred
No, not Shakey's you insensitive person. Besides having a crippling disability rendering him unable to drive without risk of damage to the pizza, he is also a B-list celebrity worth many hundreds of thousands of dollars.
Taken, not stirred.
With his goldfinger.
He doesn't need to tell him to shake the martini.