Well, first up, ass-end-on shots (the SK 767) are generally difficult to get accepted - there are some on the site, but they tend to be few and far between. Think of this restriction as the site's editorial policy
I'm afraid this one falls into the "not the sort of composition airliners.net usually takes" category - hence the "badmotiv" rejection I feel sure you will have received.
Part of the SK 767 is obscured by the wing of the CO 757 you took the picture from. You may have uploaded this picture as a "window view", but in general window views need to be pretty spot on these days to make the cut
Whilst the rays of the sun may be attractive to some, I'm afraid that they into-sun aspect has reduced the contrast in the picture, particularly in the centre around the tail of the SK 767
I would suggest with this one that you move on. You may well like the picture, and the most important thing is that you have it for yourself. Please don't take the comments above too personally - these sorts of pictures are extremely difficult for anyone to get accepted. Best I can suggest is that you concentrate on less challenging views until you've got a few pictures on here - by that time, you'll have worked out what's likely to make the grade and what isn't.
All the best,
There are old pilots and there are bold pilots, but there are no old bold pilots