Ugly is as ugly does. I think pipes that have too much shape and material unrelated to the process of smoking have a head start on ugly. They may be interesting, whimsical, or even fascinating as a small or not so small piece of sculpture, but the idea of sitting down with them for an intense smoke of an engaging blend just doesn't look attainable.
Pipes that conform to the traditional shapes more or less, but have odd lumps, bulges, and protuberances tend toward ugly, or they dive right in.
The White Spot microphone just looks like a toilet tank kit to me.
If I have to figure out where the chamber of the pipe is, no matter how cleverly concealed it may be, I'm on my way to finding it ugly.
Hurriedly executed rustication that lacks uniformity or tactile texture verges on ugly right away, as do blasts that look generally like rustication without redeeming texture.
Pipes with no grain and a matte finish that stays a sullen gray-brown concede to being ugly. A Kaywoodie Drinkless Ruff-Tone I bought some years ago was at the edge of that, but has since blossomed into a polished look with hints or red, to my alarm/delight.
One man's ugly can be another's adventure into imagination. But sometimes ugly is just ugly, no matter how you turn it.
A traditional shape carefully crafted, with design touches showing that the industrial designer or artisan carver was adding his or her wisdom to the style, these are ugly-proof. They may catch our attention or just serve their purpose, but either way, they are beautiful.