Why does Kirby's Dream Land have no copy ability?

Sakurai designed Kirby's Dream Land (1992) as a game for beginners, easy to pick up for people unfamiliar with action games. Its Kirby has a complete, deliberately small kit: walk, jump, fly by inflating himself so a missed jump never has to cost a life, inhale enemies and objects, and spit them out as stars. The only power-ups are temporary food items, Spicy Curry and a Mint Leaf, and they are a minor part of the game. There was nothing to copy because copying was not the idea; surviving gently was.

The sequel is where the idea arrives, and the record says why. Kirby's Dream Land drew criticism from more experienced players who found it too simple. For Kirby's Adventure (1993), Sakurai wanted to keep the simple gameplay and add a layer skilled players could experiment with. That layer was the copy ability: HAL created over forty candidate powers and kept twenty-five, each one turning an enemy into a moveset, lost the moment Kirby takes a hit unless he recovers the bouncing star.

So the absence and the presence are the same design philosophy at two moments. Dream Land is the floor, a game anyone can finish. Adventure is the floor with a staircase built on it, added because the audience that mastered the floor asked for one. Every Kirby game since has lived in the staircase.