It is not the process of adding something, but the process of subtracting flaws. Once we have the answer to this question, perfection, or the lack of it, can become a meaningful, useful concept. It turns out that what one person considers a flaw, another person does not even see. What constitutes a flaw, then, is relative, not absolute. The criteria we're concerned with here is Clarity.
Clarity refers to flaws in the diamond.
In general these flaws can be in the form of holes, cracks, or pieces of black carbon trapped inside the diamond. As above, we can't answer the question until we define just what we mean by a flaw. Well, I did leave one little thing out. While this may not at first seem quite fair of the diamond dealers and jewelers, upon reflection we find that they really haven't got much choice. If you're looking for flaws in inanimate objects, you have to stop somewhere well before the atomic level if your search is to have much meaning in everyday life.