Identity in a system is like the grip in this story:
“I used to watch you sometimes when you weren't looking. What struck me particularly was your interest in the grip. You knew, like every real expert, that a true player can be recognized by his grip alone. The way a man sets his hands on a club will inform you infallibly as to how deeply he's thought about the game, how profoundly he's entered into its mysteries.
“The grip, a remarkable fellow named Bagger Vance once told, when I was about the age as you were then, is a man's connection to the world outside himself. the hands, he said, are where the subjective meets the objective. Where we ‘in here’ meet the world ‘out there.’ True intelligence, Vance declared, does not reside in the brain, but in the hands.”
Steven Pressfield, The Legend of Bagger Vance: A Novel of Golf and the Game of Life
When systems are mapped from development to production, all of the design assumptions meet physical reality including users, administrators, machines, performance, QoS, and so on. The binding of identity onto claims is the individual's grip on the system. The composeable nature of the emerging identity and security standards and protocols are essential to empower architects and developers with flexibility and power to design and build identity services in a way that suits their risk management goals.