Oh man, I did the same kind of thing with a guy named Ray for like a year and a half. His sideburns always stuck out weird and I kept trimming them straight down, thinking he just had stubborn hair. Turns out he has a tiny scar near his ear from a childhood thing, and the hair grows forward over it instead of down. Once I started cutting with that forward growth, the sideburns actually laid flat for the first time. He grabbed my arm and said his wife had been telling him for years something looked off back there. Now I run my thumb along the hairline before I even pick up the trimmer, takes two seconds. Funny how one tiny spot can mess up the whole cut and you just never notice it.