A key skill in a medieval ruler is eliminating doubt, and ruthlessness is part of that. The knowledge that, if crossed, the king will respond with immediate reflex savagery, no matter who is doing it or why, is in a sense reassuring. It reassures you that any rebels who might disturb the peace will be dealt with quickly, so you don’t have to worry about lawlessness in the land. Plus, if you’re a senior baron thinking of rebelling yourself, it reassures you that there’s no point.
