I'd been a bit down lately because I couldn't figure out why my pen wasn't working well with my notebook. It would write smoothly for the first few lines then progressively get scratchier and thinner the further down the page you get. It wrote consistently on a Rhodia pad and my planner, but just wouldn't on my Midori. I just filled up the ink, so it's not that. Thought the problem was with the broad nib and replaced it with a medium size. Still ran into the same problem. Tested another pen with a medium nib from the same brand and still had similar results. Almost gave up and even mulled selling them off.
Found out this morning that the problem was the angle I was holding the pen at.