Lucille Bluth
The flu shot works against 3 strands of the flu 100%, and covers the other strands about ~60%, so yeah it isn't perfect. And the flu shot cannot cause the flu because it is a dead virus!! (so many people have this misconception idek).

I have gotten the flu the past 3 years (ever since I got the flu for the first time) and I have yet to get the flu again.