I think my problem as a photographer was loving the image, and not trying to dissect it technically.
But....that said...I've always have taken into account perspectives and lens defects and used them to make an image I desire. If you can't live with the defect, send it back. One of my favorite images is shot with an Canon FD lens corrupted with fungus. It makes interesting and, when used with forethought, insightful images.