why was this image rejected because of quality issues

Thanks, you have given me a clue - they only said it was a quality issue. But your warning on the tat is something I need to consider in future images - Thanks 

And I assume you submitted this with a model release. The hairstyle and clothing would make this image recognizable to the model, even though turned away.

Overexpose highlights and oversaturated grass are a couple of issues.

Exposure is a big issue!

Exposure

Read about exposure from the Adobe help guides.

First of all exposure. Especially the highlights. It appears to have some chromatic aberration and I believe the photo is over saturated. You may also, have Model Release problems due to the tatoo.