My photo was rejected due to quality standards. Could you please help check exactly what is wrong it? I would appreciate specific feedback on how to improve it meets Adobe Stock requirements. Thank you

Nice plant. But I’m seeing grain & lack of sharpness, due to the low light conditions. This is not suitable for commercial use.

For reference, this is what you’re competing with in Stock.

https://stock.adobe.com/search?k=donkey+tail+succulent

https://stock.adobe.com/search?k=succulent+hanging

That is a great picture of a burro's tail succulent, especially if you are growing it. From what I understand  looking at other pictures on the internet, the color should have more depth to it, but it does grow in different shades of light green.  I do like the even color you got without overexposing certain areas. I would adjust the crop so the whole plant is in the picture. I do feel this is a special example of this older plant, which some inspectors might not understand. After you make the adjustments, depending on your description, you should point out the age of the plant and how slow growing it is. I am assuming this is a real picture.

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First and foremost, too tightly cropped with respect to composition. Leave room for the buyer to crop as needed or to add text.