WRITING
Notes on the practice.
The iteration loop can only optimize things that live in your code. The user's problem might not. And from the data, they look the same.
The deli owner, the market vendor, and the problem with being known.
A deli owner in New York and a market vendor in Hanoi both do something that looks like personalization: they remember your name, anticipate your order, ask about your life. A recommendation algorithm does the same thing, and does it better. I argue that the algorithm's superiority is exactly the problem.