I can't count the number of times a client has asked me something like "I want my website to be more dynamic. How much would you charge?" I don't know! Why does anyone expect a specific answer to a non-specific question?

This usually turns into multiple back-and-forths to flesh out what the client really needs, and usually requires a lot of thinking on the developer's part (me) to nail down an actionable solution that could potentially be estimated in terms of $$$.

I was hesitant reading Trevor's article thinking what he was suggesting was devaluing dev work, but when he emphasized the importance of specificity I was on board with him. If a client has fully thought out their idea to the point of step by step mockups, that takes a LOT of the pain, frustration, and effort out of the equation which translates to the required work not costing as much.

Developers are one step away from computers (literally) and require a lot of the same rigour when interacting with them. Know what you want and be able to explain what you want (in detail) before engaging them ;)