Though for the really good designs you don't even notice the UI and bookkeeping any more.
For example: auctions are a tempting design choice when making a game, since they automatically balance the price of good and bad options available. But, they take comparatively long to resolve---so distract from the core of the game (unless it's specifically an auction game)
For example Eclipse manages to make the huge amount of bookkeeping in the game bearable with some very clever 'UI' on the player mats.
(https://boardgamegeek.com/boardgame/72125/eclipse)
Though for the really good designs you don't even notice the UI and bookkeeping any more.
For example: auctions are a tempting design choice when making a game, since they automatically balance the price of good and bad options available. But, they take comparatively long to resolve---so distract from the core of the game (unless it's specifically an auction game)
Instead some games introduce new options with a heavy mark-up and lower their price every turn. (See https://en.wikipedia.org/wiki/Dutch_auction)