Deceptive Cadences

The progression from V to I has the name “authentic cadence” and from IV to I, “plagal cadence.” A “deceptive cadence” is understood to mean the substitution for the expected progression, V-I, of the progressions V-VI or V-IV.

The effect is strong because the deceptive cadence creates the possibility of preparing the actual close again and, through repetition, of ending with increased power.