driving: on the highway, people who drive slow in the left lane, oblivious that the left lane is for passing or going fast. drivers in front of you, who slow down, and then they turn (slowly) without signalling, so you had no clue to go around them, or what they slowed down for people who brake excessively, for no apparent reason. saying: people who have no clue what they’re talking about but tell you what you “should do.”