I think that value comes from code that solves tough or complex problems, which can be humbling while improving your understanding. Feels good when you get a grasp of what’s going on and can understand that there may not be a simpler approach, just a different one.

There’s also legacy code that is not great and is not solving a complex problem but is just a product of the conditions at the time. It’s easy to look at that and assume you can do better given the same constraints, and this is neither educational nor esteem-building. Just an ego massage.