The wave lands on the beach, but it does not cease to be. It merely changes form, receding back into the ocean.
The ocean does not get "smaller" every time a wave hits the sand. Indeed, the incoming wave demonstrates, and therefore reveals, the ocean's majesty. Then, by receding into the ocean, it restores the ocean's glory.
The presence of the wave is evidence of the existence of the ocean.
Your presence is evidence of the existence of God.