Because they are constantly lied to about what 8" is.
They lie still.
A dead centipede.
Because they immediately see something about you they can change.
Pregnant.
A pizza doesn't scream when you break it in 8.
Eric Clapton would never let an 8-ball fall out the window!
They always pull out at the last second (usually to avoid a child).
Because it had a bad driver.
