Tact
Definition - The ability to deal with others in a manner that will maintain good relations and avoid offense. More simply stated, tact is the ability to say and do the right thing at the right time.
Significance - The quality of consistently treating peers, seniors, and subordinates with respect and courtesy is a sign of maturity. Tact allows commands, guidance, and opinions to be expressed in a constructive and beneficial manner. This deference must be extended under all conditions regardless of true feelings.
Example - A Marine discreetly points out a mistake in drill to an NCO by waiting until after the unit has been dismissed and privately asking which of the two methods are correct.