The last time you chose a new framework or library, was it because your problem needed that tool, or because it sounded cool and few people around you were using it? That question is uncomfortable. Technology decisions are often made for reasons that never appear in any technical document.
Same model, same conversation, same token count, and a bill five times higher. The cause is a prefix that changes, a write premium nobody reads about, and a cost curve that grows faster than the loop.
Streaming moves the wait into a connection that outlives the request. Four layers sit between the model and the browser, their idle timeouts disagree, and the smallest one ends your stream.
The badge script printed the right name for the person who wrote it and the wrong name for everybody else. Slicing counts characters, and a name is words.
Three points walk into a loop and come out identical. The list was never copied three times; the name was. A tuple makes that bug impossible.