the.com/unknown quantity

The variable everyone pretends to have already solved for.

means A person or factor whose behavior, abilities, or intentions can't be predicted because there's not enough information about them yet.

from Straight out of algebra, where 'x' or 'y' stands for the value you haven't solved for yet. The phrase jumped from math class into everyday language in the 19th century, applied first to things like untested political candidates or unproven team players — anyone whose 'value' in the equation of a situation was still a blank to be filled in.

math origin
Algebra's x, the placeholder before the proof
job interviews
Code for someone nobody can vouch for
sports usage
Rookie hype disguised as cautious scouting talk
irony
Called unknown, yet always secretly feared
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