They may be inanimate objects, but fountain pens seem to have their personality quirks. This came to me the other day when I inked my Conklin, shown in the photo.
Although it's a good-looking pen - and a nice large one, at six inches capped - it always frustrated me. It writes "wet," which I really like, and its nib is firm but never scratchy, but I seldom used it because it dries up so quickly. Nothing's more aggravating than putting a pen to paper and nothing happens.
Well, it's back to being one of my favorites again, because I discovered its quirk. I usually leave my pens lying horizontally on my desk, but I figured since this one had an ink-flow problem, I'd see what gravity could make of it. Sure enough, when stored standing on its head, this Conklin doesn't miss a beat, depositing a line from the moment it touches the paper.
Others prefer to be left on their sides or with their nibs facing skyward, and of course I have my list of "no-fly" pens, which respond to airplane pressure changes by coughing up gobs of ink. What quirks have you found with some of your pens?