Picking "the one"

Ok. This has been a problem for me. With a digital camera, you can just take hundreds of pictures, but when deciding which ones to publish/print, I always have a hard time picking "the one". I usually erase the obvious bad ones (blurry, eyes closed, etc.), pick out the favorites (maybe 10), then compare each one and erase the one that I like less until I have a managable number. I've never had a problem photographing Riley because she is pretty photogenic. Sometimes she knows it and will show off or try to make us laugh, which only feeds her desire to make us laugh more. When the lighting is the same, how can I pick which one is "best". For you photographers out there, what criteria do you use, or is there just an innate - that's the one? Hair? Eyes? Lighting? Something unique?