Rashi: Because he lacks Tevunah, he oppresses greatly. He does not heed his life, for "one who hates unjust gain will live long."

Malbim: If a Nagid Rasha does not oppress much, under his rule will be found people who profit monetarily and last. Also if he oppresses much, if he has Tevunah, he will leave the merchants who profit, and take taxes and gifts from them, and they will increase wealth for him. However, if he also lacks Tevunah, immediately when he sees a man with wealth, he kills him in order to take his money. He does not think that Ashirim and merchants should be found in his country, for he does not worry about the future.

Refer to 28:16:1:1.

Malbim: When the leader lacks Tevunah, only one who hates gain will live long. He appears to be poor - he is not in mortal danger. One who gains will not live long.