Why shadows cause rejection
A drop shadow is fine if it stays away from the edges, but if any shadow or grey tint reaches the image border, the automated check can read the background as not pure white.
Natural vs edge shadows
A soft, contained shadow directly beneath the product is generally acceptable. The problem is shadows or gradients that extend out to the edges.
Frequently asked questions
Are shadows allowed on Amazon main images?
A contained shadow under the product is usually fine; a shadow reaching the edges can fail.
Why does my image fail when the background looks white?
A faint shadow or tint at the edges may be pushing the background off pure white.
How do I fix an edge shadow?
Re-edit so the background is uniform pure white to the borders.