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

They don’t need box springs, those only exist in North America to get you to spend more money.