Weight is what creates the wave. Too much weight sinks your boat (clearly), and too little doesn’t create any wave. Before the days of surf systems and boat ballast, creating a surf wave involved stacking six friends on one side of a boat to make ballast. The bigger your friends, the better the ballast. No friends? No problem. Wake surfers would throw in some lead bags or ballast bags to weigh down the boat. But at last, boat manufacturers realized a better way to create a surf wave, and built-in fillable hard tanks and ballast bags were born. As the boats have gotten bigger and can hold more weight, the waves have increased in height, become longer, and more versatile.