Getting a dev team to understand the importance of small details

As we know, in UX design it is important to care about pixel level details in addition to the big picture. Meaning that all UI elements are perfectly aligned, correct colour, etc.

However, from time to time I get comments like "is this really important, maybe users will not notice this?" from other dev team members.

What would be the best way to get people understand the importance of pixel precision and small details? Or better yet, is there any good literature about this subject?