I have been building speakers for the past 25 years. I built my first speakers at the age of 15 using 8 watts oval paper cone full range drivers. My speaker designs have come along way since then.
At first, I needed a support for my drivers. I initially used a square box for that purpose. Then the box advanced into a cabinet, and in 1999 it became an enclosure inspired by nature with no corners or sharp edges. Like a fish gliding effortlessly in the water.
This enclosure design performs better in your listening room than an all flat cabinet surface.