What is the most annoying habit of people?

What is the most annoying habit of people?
Updates
1 y
Most opinions seem to be about people being loud on the phone in public, which is indeed the basic action of idiots. But I also loathe:• People who walk too slowly, especially when I'm in a hurry.• People who insist on paying their huge grocery purchase in cash making the entire line wait for them to receive change. (Be normal, use your credit card!)• Pseudointelectuals • Idiots who always pay more than 10 items on the 10 items max line.
What is the most annoying habit of people?
Post Opinion