Boxers. I've met some (either really excellent show quality, or Boxers who are so far from being up to breed standard they could be called Pit Bulls) who are stunning. But, many more who are bug-bloodshot-eyed, have twisted faces, crusty noses, weird jaws, scream bloody murder, have snot/dirt constantly flying from them. Paired with gangly legs that are hurled at your chest 99% of the time. I know they are one of the breeds that is supposed to look silly, but I couldn't see myself living with that. I used to want one! But after spending time with thousands, the vast majority terribly bred, I am past that phase.
Any dog that snots and snorts is not my thang. There are some flat-faced dogs that I really love, but in general I wouldn't want one. I don't mind drooly dogs, but snot is nasty. Brache's with long noses, although conformationally "incorrect", I like. It saddens me that dogs are purposely bred to have all of those health problems.
Show and BYB German Shepherds... oh lordy!
Most Labs... I'm just used to seeing sooo many poorly bred Labs. Most of them look like a weird assortment of body parts; curly tail, tiny shrunken head (or giant Rottie head!), fat body, long legs, incredibly swayed back. Most look like mixes. When I see a well bred or even well-put-together Lab it surprises me! A well-bred Lab is a breath-taking dog, but a rarity.