A set of related things offered together. A suite is designed to be used as one, not merely sold as one.
Old French suite (a following, a retinue), from Latin sequi (to follow); a set of things offered together kept the sense of items that follow one another naturally, meant to be used as a train rather than sold separately.
A set of related things offered together, designed to be used as one rather than merely bundled for sale. Each part follows the others, the way the old word for following implies.