Normative Signs: The Poetry of "Ought"

This is quite a different kind of normative sign. It’s a pictogram showing how to use a piece of exercise equipment, namely an ergometer (rowing machine).
I suspect there are 3 implicit messages, here.

• Here’s how to get the most out of this exercise.
• Here’s how not to get hurt.
• Here’s now not to end up wanting to sue us (the gym owners or makers of the machine.)

(Photo courtesy of Sam B.)