What is perfection? Trying to answer that is like trying to explain what is love (you may try but you won't be able to ever cover the entire subject for everybody!). Yes, we do use extendedly the word "perfect" on many occasions like a human reflex in face of a particular context or subject that may greatly impacted us. In photography, perfection is tabou because generally we don't accept that anybody can produce something perfect or near perfect except for some very rare pictures issued from reckoned master photographers.
If there is no perfection in this world (that is still looking for!), but there is a lot of "imperfections" which, in my sense, represent the real essence of humanity by its diversity and originality. If you ask me, I have a tendency to avoid the stereotypes induced by perfection especially with people. In a way, perfection is not realistic as it should be desirable. Differences are part of our cultural heritage. It is part of our unique identity and imperfection can be observe in the nature of this universe.
In this fascinating world of photography, imperfections are observed into different narrative levels both technically and esthetically. In each case, it is a highly personal interpretive analysis because it depends which specific perspectives and references you are using to do so. For example a blurry subject or context in a picture can be acceptable if it is part of the intention of its author by suggesting movement or any other emotion involved when you are looking at it.
Imperfection is often associated with derogations from the artistic traditional pattern imposed in the picture treatment. Composition is a good example of it because if you are exceeding the proclaimed rule of third to position your subject, you may be considered as an anathema in this wonderful photographer world. So. perfection is dividing your frame by three horizontally and vertically "zones" that are creating four line intersections for specific points of interest. But with time and observation, you may discover that the eye can travel very erratically when it is scanning a picture in its deep. So, the rule of third may be dismissed in profit of different subject distributions.
We can argue the same distressing point of view about the so-call exposure accuracy for a specific light context. For example, strong contrast associated with black and only white tonal grades can create beautiful silhouette effects. The choice of how you want to "expose" your subject is only revelant of which final rendering you are looking for. And so again, imperfection is becoming a kind of perfection f its own.
You can go further by discussing about focus or unfocus, clear or blurry, color accuracy, etc. All these are part of the photographer own interpretation and experimentation. They can emphases the author emotions upon his/her photographic subject. And finally they can provoke to his/her attended auditoire different retroactions for the everybody beneficial. Photography is an art and as an art, all kind of "imperfections" can be reached over times and over people.
Photos Daniel M: Panasonic Lumix G95 / G Vario 12-60mm Power OIS