Simple -
The bigger the driver, the sloppier the sound for any particular material... ie: bassists that like a tight punchy sound use 8" or 10" arrays in their cabinets, whereas the sloppy bassists (I'd post names but every time I do I offend someone) usually play through 15" arrays.

So next time you see some kid on the street with one of those farty cars with the 20" basket sub... give the bass a listen alone, it'll sound like bean night in Attica.

Bren R.