> I can't think of a reason why a developer (who's not involved in the UI or UX stages) would need to change anything, even by a pixel. I guess you supply your

> I can't think of a reason why a developer (who's not involved in the UI or UX stages) would need to change anything, even by a pixel. I guess you supply your developers fully documented fluid-resizable, responsive, dynamic mockups with all possible states? That’s one lucky developer. As a designer and developer, most (extremely talented!) designers that I end up working with still send me their designs as static PSD’s, and they also don’t understand enough HTML to know which design-choices are costly and which are not, and which don’t scale well with the screen / text / content, etc. If the designer and developer don’t work together at the UI/UX stage then it’s completely understandable for the coded-up site to not be a pixel perfect carbon copy.