Not everything that's measured is important. And not everything's that's important can be measured.

"What gets measured gets managed. But I’m saying something stronger here. If we are not careful, what gets measured is all we manage. We don’t just pay more attention to what is in the light. We forget what is in the shadows. We forget about the rest of the things that do not get captured in measures we become accustomed to studying and using.
    "Our desire to quantify complexity seduces us into ignoring [valuable] things that are less easily measured.... Other factors get forgotten [whose] effects, if real, are virtually impossible to quantify.... These intangibles are hard to keep in mind....

This is one of the first mistakes we can make with [a raw number] — we forget that it only captures part of what we care about. The other mistake we make is that a measure isn’t the thing itself...."

~ Russ Roberts, from his post 'Apples and Oranges: A Critique of Utilitarianism'