Sertorius (18.6-19.1)

Sertorius spared their lives and let them all go, but he burned down their city,[*] not because he was angry or cruel, for he appears to have given way to passion less than any other general, but to put to shame and confusion the admirers of Pompey, in order that it might be said among the Barbarians that though he was near at hand and all but warming himself at the flames of an allied city, he did not come to its relief.

It is true that Sertorius suffered several defeats, and yet he always kept himself and his own forces undefeated, and got his crushing blows where other generals than he were in command; and from the way in which he repaired his defeats he was more admired than the victorious generals opposed to him, as, for instance, in the battle on the Sucro against Pompey, and, again, inn the battle near Tuna against both Pompey and Metellus.