What is the most common reason people miss a top pair in a judging class?

“Usually on a top pair of livestock make sure to prioritize a different set of traits than the officials.”

For Example:

Using a heifer that is much more feminine with less body and rib over a more common fronted heifer that is very broody when they are both of equal quality in other aspects.

Sometimes, in a “big cut” top pair, it is losing sight of the “big picture.” In other words, finding the best livestock in the class to start, even if they are not personally “your kind”.