A Wave is symbolized as one of the strongest forces on earth. so strength for one. also if you read more into it, its about faith, a wave is you against mother nature, you cannot control it, you just have to put your faith into it.
They are geometrical forms which are said to act as a template from which all life springs. They are named after the ancient Greek philosopher Plato. To the Greeks, these solids symbolized fire, earth, air, spirit (or ether) and water.