Sturgeons L

Sturgeon's law (or Sturgeon's revelation) is an adage stating "ninety percent of everything is crap". It was coined by Theodore Sturgeon, an American science fiction author and critic, and was inspired by his observation that, while science fiction was often derided for its low quality by critics, most work in other fields was low-quality too, and so science fiction was thus no different.[1]

Source: Wikipedia