The line is associated with Bruce Lee, the martial artist and actor whose philosophy used water as a symbol of adaptability and formlessness. The full idea, that water takes the shape of its container, became one of his most quoted teachings and was repeated in interviews, books and documentaries about his life. Online, the short phrase detached from the longer explanation and became a standalone motivational clip, shared in fitness, study and self-improvement edits. Its staying power comes from its simplicity: in two seconds it offers a complete mindset shift without needing any context.