Agree.

My sales have slumped there and I don't feel like uploading anymore.  Their review policy baffles me, buyers like a bit of choice and reviewers aren't good at picking what sells and what doesn't.  They must be losing a small fortune because of this policy and it demotivates contributors.

I am not worried too much about bad policies at any specific site (DT is not the only one): if buyers can't find the pictures they need, they'll either buy another picture or go somewhere else. And being independent, there may be some price difference but in the end a sale is a sale, no matter where.

I am confident that in average bad policies are worse for agencies themselves than for us contributors. They will either realise and change, or die - their choice.

I agree.  My percentage of approval varies widely among the sites to which I contribute, as do the photos which are accepted and rejected.  What gets rejected on one gets accepted on another, and vice-versa.  Ultimately, I get all of my photos uploaded and available on the web.  On the few occasions I've had to be a buyer, I did what I suspect most buyers do.  If I didn't find what I was looking for on one site, I went to another.

It's interesting to note that I was producing videos in which I needed various still photos, and I needed a variety of different shots of the same subject (alternate angles, varied focal lengths, etc.).  Thus, if a particular site had only one or two shots of a subject, I went to other sites hoping to find more.  I think DT and others really need to get over this "similar material" rejection policy.  But then, they certainly don't make decisions based on what I think.   

I cannot understand why sites don't realize the value of rejected images.

If I owned a site I would accept in a special pile all those rejected by my reviewers. Then I'd make them available in a sort termed "User's Choice" or some such name with a disclosure saying something like "Different from our regular selection but you be the judge".

My site would benefit by having an instant boost in images available, happier contributors because of the chance for all submitted images to be sold, and an ironclad way for the sites to analyze their normal review processes.

...and soon they will only accept one file per model 

or a picture with 10 different poses into 1 picture, there are photographers that do that and that�s not my business but I don�t agree, I have a few myself with objects isolated and don�t feel they sell better than separated..