Why is the plastic chair through a circular hole with a little
Plastic is malleable, and when it sits under pressure, the plastic extends in all directions to accommodate the faint extension.
Just like a railroad track, there is a little space left between each section of the track, because the rail (metal) is heated and expands because of heat expansion and cold contraction. This gap is meant to give space to this expansion. Just because the track is deformed by temperature, the plastic chair is deformed because of the forceBut if there are no holes, pile up after not easy to get open, easy to absorb.
