Healthy variation is the raw material that natural selection feeds on, but there are plenty of reasons why evolution might not arrive at one isolated perfect version of a trait or behavior. (sciencedaily.com)
He looks like a less - than - perfect version of his former self but is very much in line with the ugly vegetable movement. (mindbodygreen.com)
This means that authors of complex texts with diagrams and the like will have to spend money up front to have a designer create a pixel perfect version for CreateSpace and then risk endless re-dos as it is dinged again and again. (techcrunch.com)