15 Drink water from your own cistern,
    flowing water from your own well.
16 Should your springs be scattered abroad,
    streams of water in the streets?
17 Let them be for yourself alone,
    and not for strangers with you.
18 Let your fountain be blessed,
    and rejoice in the wife of your youth,
19 a lovely deer, a graceful doe.
Let her breasts fill you at all times with delight;
    be intoxicated always in her love.
-Proverbs 5:15-19

Remember that Proverbs doesn't just help us learn wisdom. It also teaches us wisdom from Solomon's experience.
Remember that Solomon did not rejoice in the wife of his youth. Instead, he collected wives, 700 of them in fact, with 300 concubines as well.

The king invites us to compare what he did to what he teaches. He can speak from experience when it comes to polygamy, and what is is answer when meditating on it? He does not tell his son to do as he did and collect multiple women. Instead he praises the man who has ONE wife and is satisfied with her alone.

Not only satisfied, but intoxicated; Solomon will hear none of the nonsense objections that men bring up about getting bored, needing variety, dead bedrooms, etc. Having experienced more women than any man could dream of, he upholds that an exclusive marriage between a single man and woman is BETTER than what he has.