Color faded on the shelf
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Paprika that was red in your store is orange in the customer's cupboard. The weight is right, the flavor is mostly there, and the product looks old. This one is almost entirely a packaging decision.
The pigments that go
Carotenoids do the fading: the pigments that make paprika, chili, turmeric and annatto the colors they are. They oxidize, and oxidation is irreversible. Anything you sell primarily on its color is on this list, which is an uncomfortable overlap.
Light is the accelerant
Oxygen does the damage and light speeds it up. A jar on a windowsill or under a shop spotlight fades in weeks; the same jar in a drawer takes many months. Heat adds to it, so the rack above the hob is the worst place in the kitchen and is exactly where people keep spices.
Note this is the opposite failure to the darkening you get at the mill. Heat at grinding makes powder darker; light on the shelf makes it paler. Both are described as color problems and they point at completely different parts of the process.
The clear jar problem
Clear glass sells spice. The color is the display, and a wall of bright jars is the reason a customer picks your brand over a carton. The same clear glass is what fades it.
There is no resolution to that tension, only a choice. Faster turnover tolerates clear glass; slow-moving lines and anything sold online into a cupboard do not.
What to change
Amber or opaque for the pigmented spices, clear for the ones where color is not the product. If the range has to be visually consistent, pick the packaging that protects the most vulnerable member of it rather than the one that flatters the average.
Then keep your own stock out of the light too. A faded jar on your market table is doing the work of an advertisement in reverse.