I have seen so many intances of material waste in construction, because the design calls for something moronic. I have seen masons cut bricks to 7 and 3/4 inches long, due to some stupidity on the part of the architect. Electrical engineers don't even consider where, precisely, wireways need to be run, it gets left to the field electrician to decide. Isn't there software for this stuff? Don't get me started on the conflicting drawings of equipment placement between trades... more than one sprinkler head has been moved for light placement, and vice-versa.