"Adam's Law #1: The Yamanote Line"

This "law" basically applies only to Tokyo's Yamanote Line:
If the train is crowded, wait for the next one because it will be less crowded. The Yamanote comes so often that one train tends to fill to capacity, while the next one will be less so.

Please note: This is not a metaphor, merely the observation of someone who has taken the Yamanote Line for almost eight years in total.