For me personally it’s the combination of high price and the blinding, paralyzing, cancerous, caustic and ungodly level of hideousness. They truly are monstrosities that should be taken hunting and then "accidentally" shot in the face with bird shot at extremely close range.
They truly are the type of speakers that you have to listen to with your eyes closed, not because you are taken away into another dimension by their sound quality but merely to avoid going blind.
These are the type of speakers that you love with the lights off.
Sure there are many "ugly" speakers out there, but Wilson audio the are champions with complete dominance over the category.