The Higher the Value, the Harder the Hand (Article ID 42)
Abstract: Jokerless hands under the Singles and Pairs section of the card have the highest values on the card. Obvious reasons being, you must complete the hand through your picking, cannot use Jokers, and you cannot call a tile for exposure unless it is your last tile and completes a hand for mah jongg.
Question from a player: Why do jokerless hands have a higher value?
Answer from the NMJL: “Jokerless hands must be completed by discarding any jokers and are comparatively easy unless they are played jokerless. therefore, they are paid top limit because of this sacrifice.”
Source: National Mah Jongg League Bulletin Q&A (1972 page 4) https://www.nationalmahjonggleague.org