Ask HN: Relationship Product Manager - Developers

Could some developers active here on HN, explain which is the best way for us, product managers, to communicate a request to you guys so that there is absolutely no room for equivocation?

Example:

I had a request for one my developers (he does some graphic design and CSS) to do a simple page with 3 boxes inside. the boxes needed to be designed. Nothing fancy.

I even, as a product manager, did a full explanatory mockup (in Balsamiq which I highly recommend btw) to make the developer life easier.

What do I get in return? The page fully coded. The boxes? Copy and paste from the Balsamiq mockup. (WTF? I'm not sure if to cry, laugh or kill someone)

Please don't tell me that I really need to explain to every developer that if something is for a website that is fully branded, with high end design, and I come along and show something that looks like a 5 year old draw it, nobody will at least ask: does this makes sense? Is this guy nuts to want to include this design on the site?

Do you guys really think like you code?

P.S: As a product manager (and this might not be the case for everyone) please developers, take an active roll in the product itself. Make yourself heard in the design, marketing, features, etc. It helps a lot and it helps the product. You are the most active users of the site and we need your feedback.

Please forgive my english as is not my native tongue.