What is lane courtesy, and what etiquette does USBC expect?

USBC's etiquette guidelines:

• One-lane courtesy: if you and the bowler on the next lane reach the approach at the same time, the bowler on the right goes first. Stay off the approach while you wait.
• Be ready when the pins are set, but wait until the pinsetter finishes its cycle and the sweep bar is up before you throw.
• Don't take too long aiming or setting up on the approach.
• Stay in your own approach area while delivering, and step off once you've thrown.
• Keep movement and noise down when others are about to bowl.
• Avoid excessive lofting; it damages the lane.
• Ask before using another bowler's ball.
• No abusive language or obscene gestures, and be a gracious loser.
• Wet shoes are a safety hazard, so watch where you walk.

Separately, USBC rules prohibit putting any foreign substance on the approach or using shoe products or soles that leave residue on it.