Office Chair: The Offset AxleWhy the wheel is never directly under the pivot.

From the show

Why it looks like that

Ever notice that the wheels on your office chair or a shopping cart are not centered directly under the mounting stem? This deliberate misalignment is the only reason you can steer. This episode breaks down the physics of "caster trail" and how a simple gap between the pivot and the axle forces wheels to obediently follow your direction.