A common misconception I long held is that core devs of a product must be the top product experts.

The reality is that, as a core dev

• there isn’t enough time to be both a dev and a user
• knowledge of the implementation taints you and can prevent you from seeing the product clearly
• it’s extremely difficult to focus deep on the details, and also view the product from a high level, holistically

Yes, you will have the absolute expertise on certain product behaviors or possibilities. But almost certainly never for the whole product at once; just the part you’ve been working on lately, where the knowledge is most fresh.

This is why it’s so important to surround yourself with “power users” — those that are untainted and unburdened by the implementation, and can use their full mental power to absorb and innovate on the product simply as a product.

These are often the people that find the most interesting uses and abuses of systems, that the core devs weren’t even aware of.

This can happen for any kind of product, including and especially programming languages. Many of the interesting programming “patterns” are created not by the developers of the language, but by “power users”.[citation needed]