This isn’t to say we should never deviate from normal graphing conventions, but we should have a good reason for doing so—a reason that makes up for any unintended consequences.
What other design decisions might also take our audience by surprise—going against normal graphing expectations? I’ll outline a few.
Click through for examples. One thing not explicitly brought up is that we follow conventions to reduce the amount of thought needed to understand something. For circumstances in which there’s a major benefit, you might want to run that risk. Also, there’s an argument in here that, at some point, it’s better to have something radically different than marginally different.