The problem with economic approaches to valuation is that the current ordinalist economics does not measure value - it measures price and then conflates that with value at some point, while having nothing but a subjective model for price, because it wants to influence policy.

Or, you could say that it is in large part foregoing objective measures of value and welfare that is at the heart of the problems caused by modern economics. As in, it is clear that $5 worth of tap water is more valuable than $5 worth of movie tickets, but neoclassical economics refuses to make that distinction.