"They should be designed in a way that they just work -- they are easy to use and use without error." But how do you learn how to do that? For example, making

"They should be designed in a way that they just work -- they are easy to use and use without error." But how do you learn how to do that? For example, making an API. API's, once released into the wild, should never be changed (unless your hugely popular like Facebook). Public changes breaks code. I look at some of the most popular API's. They look easy but I don't know how they got to that point. They had an infinite amount of choices yet they choose that particular way of doing it.