There are also situations where a sticky note can be a vital piece of safety equipment because an instrument is malfunctioning. And even though the pilot knows the instrument is showing bogus data, they're so used to looking at it that they will instinctively do so and react to its bogus indications, so the safest thing is to hide it from view entirely. Fortunately there's enough redundancy in the information from the basic instruments that even if one of them fails, you can still fly the plane by extrapolating the missing information from the other ones.
Though I suppose in this stretched analogy those are not great positions to be in.