Proverbs 20:14 - Joseph Benson’s Commentary on the Old and New Testaments

It is naught, it is naught. The commodity is but of little worth; saith the buyer Namely, to the seller; he discommends it, that he may bring down the price of it; but when he is gone his way Having purchased the article upon his own terms; then he boasteth That by his subtlety he hath overreached the seller, and obtained a great advantage to himself, and he laughs at his simplicity in selling it at so low a price. This Solomon notices as a common but very blameable practice.