πείθεται πᾶς ἥδιον ἢ βιάζεται (Dio Cassius, Historiae Romanae 8.36.3) → it's always more pleasant to be persuaded than to be forced
P. and V. οὐ προσήκων, οὐ πρέπων; see unfair.
excessive: P. and V. περισσός.
undue influence: P. and V. πειθώ, ἡ.