Why you should have a home inspectionon on a brand new home. Builders hire subcontractors who are usually the lowest bidder and sometimes don't produce the highest quality of workmanship.
I recently did a new home inspection on a $1 miilion + home and found numerous issues that needed to be repaired and utilities that weren't installed properly or completely installed.
Here's a video that describes a situation that new home owners found themselves in unfortunately. Old or new homes should always be inspected by a licensed, qualified, well expereinced Home Inspector preferably with previous home construction background.