How we cite our quotes: All quotations are from Rocky.
Quote #1
ROCKY: A southpaw throws your timin' off, see? Other guys, it throws their timing off, it makes 'em look awkward. Nobody wants to look awkward.
Rocky's left-handedness gives him an advantage in the ring, but in boxing, advantages are often seen as disadvantages. Most men want a fair fight.
Quote #2
MICKEY: Marciano... He had the same problem and this string cured it.
Mickey knows he can appeal to Rocky's competitive nature by name-dropping his idol, Rocky Marciano.
Quote #3
MICKEY: The idea is that if you can move and you can hit without breakin' the string, you got balance. You become a dangerous person.
This is a boxing movie, so we need to see Rocky training for the competition. Most of the time, he trains in montage, but this is a unique trick Mickey does to help Rocky with his balance.