The timidness I've seen called out is when a person in a maneuverable aircraft is afraid to engage and get a litle dirty.
An example: I'm in a 38, and a higher 38 comes and starts to dive on me. I try to equalize E states, but still know that he has more speed built up. I'll break down and left at some point when he's almost in gun range, hoping to induce an overshoot. He doesn't bite, but instead of doing something like a high yo-yo and staying within 1.2k to 1.5k off of me, he zooms up to 3k and the process repeats itself, basically resetting the situation, often allowing me to gain altitude in the process.
Then, after the altitude advantage is nearly negated, the enemy 38 flies away from the fight, but reverses each time I try to break off and go elsewhere.