eli5 Why Mattresses need frames and box springs for (stability) when the floor is a fully flat surface?

Question

I haven’t found anything scientific about this, but box springs are wooden slats sideways for even distribution of weight, but wouldn’t the floor be better? Does it damage the bed or affect sleep?

Or are box springs a solution to the manufactured problem of raising beds on bed frames?

In: 1254

Answer 1

Because most people don’t want to sleep that close to the floor. The box is needed if you are using a bed frame, because the mattress isn’t rigid enough to put in the frame by itself.