Contradiction with Ecclesiastes 8:14
This verse questions why good happens to the wicked and evil happens to the righteous, suggesting life's unpredictability which contrasts with Proverbs 5:21 where it implies paths are fully known and overseen by the Lord.
Ecclesiastes 8:14: There is a vanity which is done upon the earth; that there be just [men], unto whom it happeneth according to the work of the wicked; again, there be wicked [men], to whom it happeneth according to the work of the righteous: I said that this also [is] vanity.