Until I am measured I am not known, Yet how you miss me when I have flown.

Common Wrong Answers
“Money”
Money can be measured and spent, but it is not something that flies away in a literal sense like time does.
“Love”
While love can be difficult to quantify and people often feel its absence, it does not have the same notion of 'flying' away as time does.
“Dreams”
Dreams can be elusive and often feel lost, but they do not have a concept of measurement in the same way time does.
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