Fibrillation.

Fabric fibers work their way up through a thin ink film after the garment is washed or tumbled, breaking the surface of the print and dulling it. The ink has not come off and it has not cracked; the garment's own fibers are standing up through it, which is why the fade is even across the whole print rather than the spotty, uneven loss you get when an undercured print washes out. Fleece, heathers and open knits raise fibers most, and the fix sits on the print side: more ink on the shirt, an underbase under the color, or matting the fibers down before the deposit goes on. It reads to a customer as a print that died in one wash, and it comes back as a claim on garments that passed inspection looking perfect.