The wheelchair parked beside a swimming pool interrupts a stranger’s assumptions about what movement looks like.

The chair beside the water contradicts an assumption someone had not noticed they were making. Movement, ability, and what a body can do turn out to be far more varied than the picture people carry, and the correction arrives as a small jolt. Assumptions are usually invisible until something interrupts them.

Welcome the jolt when it comes rather than smoothing it over. Notice the assumption you just had, and let it be revised without commentary. And in practical terms, be someone who asks what would be useful rather than deciding what someone can or cannot do, since the answer is theirs and not yours to estimate.