If a question says “choose up to three,” the interface should make that rule obvious while the participant is answering.
Questions with a maximum number of selectable answers communicate that constraint to participants so they know what is expected before they continue.
As participants make selections, the interface enforces the maximum immediately rather than letting them remain in an invalid state and discover the problem later.
The benefit is simple: clearer instructions, clearer feedback and fewer unnecessary corrections while answering. That helps participants complete the intended response state faster.