Wallpapers that aren't deemed high enough quality (for various reasons) go to your personal gallery. We all have them. Sometimes they rate low quality for reasons like, they may be too busy for useability. Maybe a tad blurry, if it's a photograph. I think 3 mods vote on each wall. I have personal page only walls, and I'm a master. So don't be discouraged. It happens to all of us.
Yeah, I just thought that my very recently uploaded wallpaper was one of my better ones yet it didn't even get accepted to the public gallery.
Oh well.
And reading those uploading guidelines, I guess my wallpaper had too distracting colors, but not even getting it accepted to the public gallery feels kind of absurd since I'd say it's really top quality besides that and works great as a wallpaper. And it also feels kind of limiting in what kind of wallpapers you can make.
BUT, no worries, I have many other projects in the making that hopefully will get accepted 
