Too much AI images have been rejected

Sorry, but I do not agree. I would say that too many bad assets get accepted. We have seen some terrible assets that are open for sale. 

Now let us focus on your asset (all screenshots are at 100%).

Upper corner, left:

It's unsharp and you see at 100% artefacts.

A bit more to the right:

This is a severe aliasing problem. Seeing this at 100% in this detail lets me think that you have a severe upscaling issue. You see aliasing everywhere, I won't take a screenshot of all cases.

Down, left:

Structure on the leaf needs to be corrected. I wouldn't, however, say, that this is a major issue.

Middle left (200%):

This looks like a bad cutout work.

Check your assets at 100% (and 200% or even 300% if you see an issue) before submitting and correct what is corrigible, and your failure rate will go down. If you can't correct, don't submit.

If you are new to stock, you should consider these resources: https://helpx.adobe.com/stock/contributor/tutorials.html
Please read the contributor user manual for more information on Adobe stock contributions: https://helpx.adobe.com/stock/contributor/user-guide.html
See here for rejection reasons: https://helpx.adobe.com/stock/contributor/help/reasons-for-content-rejection.html
and especially quality and technical issues: https://helpx.adobe.com/stock/contributor/help/quality-and-technical-issues.html

Some minor anomalies in the way some objects were rendered. The number of petals differ per flower. And as @RALPH_L suggested, sharpness could also be an issue.

Contrary to Ralph I think the sharness is ok. But the leaves look thick because of the shadows and some have four petals and some have five. Also, some of the yellow leaves are not seated correctly and some of the green leaves are missing the tip.

The focus on this image is not sharp.