I’ve been watching Wimbledon this week. Mexican waves travel around the centre court when the crowd gets fired up. But sometimes they die halfway around.

If you’ve ever felt annoyed about something, or believed in a cause, or heard someone else ask how they can make a difference, think of a Mexican wave.

No single person makes it happen, but if everyone sat back, accepted the status quo, and did nothing, it wouldn’t happen. One person truly can make a difference when they’re part of a crowd that’s working together.