Why Do Symphonies Build to a Crescendo?

Imagine you are climbing a very long staircase. At the bottom, it is quiet and calm. As you go up higher, your heart beats faster and the view gets bigger. A symphony works the same way! It starts with soft notes like a whisper. Then, more instruments join in, playing louder and faster. This is called crescendo. It means getting louder step by step. The music builds up energy, just like you building up speed down a slide. Finally, it reaches the top where everything is loud and exciting. That is the climax! Then, slowly, the sounds fade away like clouds disappearing in the sky. Musicians practice this so the audience feels happy or excited without knowing why.