Hello XXXXXXXXXXXX
Leaving the mattress and box springs on the floor would not hurt either, but it would make the bed surface lower to the ground, and most likely harder to get out of. The bedding would not hang as it does on a bed that is on a frame. On a positive side the floor would provide very good support and you would never have to worry about the mattress falling out of the frame. Many people put the mattress directly to on the floor without using box springs.
Philomath
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