It’s a pretty good example of a few things.

Starting from left.

Ear 1 & 2 lack of fertility early on.

Ear 3 severe pollination issues - no fertility problems.

Ear 4 and 5 - ran out of fertility around tasseling.

Ear 6 moderate pollination issues - looks like the plant germinated late.

Ear 7 is immature

Ear 8 - tip back - either genetic or linked to planting density/light levels.

Ear 9 - on the edge with full light and adequate nutrition.