Composition
I find the composition here intriquing, especially when combined with the title. The totally centered composition makes the photo a bit static, and it's very obviously a "look at these" presentation. There's nothing wrong with that, but I wonder if a slightly angular presentation would have helped created some depth. I find the dirty fingernails to be consistent with the message, even though some commenters didn't like them. It would seem ridiculous to me to have a child picking up rocks and not having dirty fingernails or hands. Someone missed the message, but if these comments were made during the challenge, they didn't have the benefit of your comments to explain the "collecting" nature of the shot. Remember, all they have during voting is the title and the photo, and that probably hurt your score quite a bit here.
Background
Your background is limited to the pink check pattern, and it's very "flat". Again, some type of angle to lead the viewer's eye around and create some depth would probably help quite a bit.
Camera Work
This looks like you used a fill flash, and the light is a little bit harsh. I think simply doing this in good daylight would have been better. The flash has created some glare here that makes for unnatural skin tones.
Post Processing
This appears to have limited post processing, just from my observations. I would think that some curves adjustments (or a simple contrast boost, depending on your software) would darken the background just enough to improve that feeling of depth that I keep harping on. The image is also rather pink in cast, and I did a color balance adjustment that made it seem more "natural" to me, which helped quite a bit. After that, I personally like to do an edge preserving smooth to eliminate noise and then do an unsharp mask to bring the "edges" back to life.
My Opinions
Normally I don't do this, but I've taken your shot and done some of the edits I discussed. I personally think this is an improvement, but I definitely understand that you may not think so and I will not be offended by that. I hope you find my thoughts to be helpful and informative, and I hope this critique helps you in the future.
great title! love the idea! a sweet, simple composition. the lighting feels a bit harsh and direct, and makes the hands look a bit shiny to my eye. i wonder what bounced or more indirect lighting would do to the feel of this photo?
The dirty fingernails are a nice touch (seriously), even if unintended. :-) The lighting is a tad flat, some dramatic lighting and I think you'd have a 9 on your hands.
Sweet. The strong lighting (flash?) produced hotspots on her fingers and stark shadows under her hands. If a softer lightsource had been used, the pic would have been more emotive.