It's not a guideline but we don't know if that's the reason either, and the voter didn't have to do it with that level of specificity. He merely had to believe that 10 guys who have been eligible longer were more deserving of his vote at this point in time. There's also no rule against just saying, "that guy doesn't need my vote." Clearly this is part of the voting process every year, just in a less noticeable/notable way.
You're either in the Hall or you're not, they don't keep score.
I do agree the votes shouldn't be anonymous.
It's also no less possible that someone just forgot or made a mistake.
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