Would be easier to reply if the EXIF data was there.
Flat lighting that does not define shape, not sharp, too shallow depth of field as for the subject IMO(the leaf is out of focus for example- it can limit usability of the file I think), lot of white space(I think buyers don't like to by white space- they can easily create one

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By the way you put the watermark on white space(???) cutting the foto in half cuts off the watermark and creates nice vertical composition!!!
(Edited on 2012-12-08 02:18:16 by Mijau)
(Edited on 2012-12-08 02:18:53 by Mijau)