I answered as objectively as I could, in part based on helpful feedback from clients (it makes it easier when my client tells you which photos he thinks are outstanding, and the list matches my own). When I considered the percentage, I did not include images with tech issues (missed AF, people turning heads at the wrong time, etc.) but only those I considered "keepers".
The thing is, if I take 500 photos of a concert, I usually have about a 90% keeper rate. Are all the photos "great"? Of course not, but I keep that many because I never know what an artist may request to use. One manager asked for permission to use an image that was technically the weakest of the set I published because he thought it best captured one aspect of the style of the show. It was true, even though the photo included subject motion and some noise levels that a lot of people would have seen as reason to delete the photo.
Therein lies a bit of a conundrum of determining a keeper, much less a "great" photo. That is, a combination of the experience and expectations of the photographer. I've encountered people who think some very mundane, uninspired images images are "great" because they are technically well done. On the other side of the fence I've seen people tout technically bad images of theirs as being great, simply because their ego and emotional attachment to the image leads them to that opinion.
I personally consider only a handful of my images great when I compare them to iconic images of true masters. By contrast, I have many people who declare entire galleries great because of their lack of experience. Where does the truly accurate assessment lie?
What I'm saying is some people don't know what a great image. I had a friend ask me to critique what he thought was the best photo he'd ever made, prior to him wanting to enter it into several photo contests. I asked him if he wanted an honest critique and he insisted. So I pointed out a number of flaws, both technical and aesthetic. We exchanged emails about the flaws,and how he could overcome them in the future, but I know he was disappointed when in essence I told him I would have deleted the photo.
If there's any doubt of how easily people overrate our own photos, take a look at the DPR challenges forum and the indignation expressed when some people don't place as highly as they expect. On occasion, they are right: the voters obviously went for the "Thumbnail Judged, Top 40 Eye Candy Shot" and overlooked some photos that were quite good if viewed critically. In other cases, the aggrieved photographer really entered a piece of dreck, but is unwilling to recognize it as such.
