I hate witches, especially when I first played L4D in singleplayer.
I kept using voice command to say "WITCH!" and my AI teammates were all like "Kay we heard you the first twenty times." So I'm like "Kay we sneak around". Half way around her, I see "Louis has startled the Witch!" and she's running at me like a kamikaze bitch. Automatic shotgun didn't do stuff on her, and now I hate Louis.
Oh, and Zoey is a bitch and takes medkits when I'm about to pick them up and use them. Then Bill just whines about how he is old.