Quote: - The image dimensions were too small. Only scans with 1,000,000 or more pixels are allowed. You can calculate the amount of pixels by multiplying the width of the image with the height.
- The scan contains excessive artifacts. This includes, but is not limited to, page folds, dust, noise, text or other markups on the image. Scanned images need to be scanned at least at 200dpi to conform to the quality demands required on Minitokyo.
- The image was too blurred. Only sharp scans are accepted. Please do not attempt to 'filter' scans in Photoshop, as this usually further reduces quality.
- The featured character was not visible enough, or unusable for wallpaper purposes.
-The majority of the image features either blank space, magazine text, or multiple under-sized images.
- The scan did not feature an anime-style image. See this announcement for more information: http://forum.minitokyo.net/showthread/35992/

I think there's a mistake

No there isn't.
The dimensions of the actual characters (the wallable part) on those scans do not meet the size requirements.

Oh, so that's the reason, ok.