So I wanted to try persnicketyprints services for and hybride project I saw at thehybridchick ... I registered and started the upload process ... They have this scale on each pics that show-up letting us know the "quality" and the size that this pic can be printed at for best results ... I'm chocked to see that my last LO (done one PSE8 600x600pi, 12x12inch, 300pi/in) shows 3 "red squares" meaning not good to print bigger than 4x6 !!!???

What's going on ???
What should I do ???

Thank you for your answers