Time is a construct of collective imagination, much like money. The notion that it can be wasted is rooted in the fact that we, each in our own manner and moment, will die - a fact that few are truly comfortable with.
This discomfort is magnified by the realization that, with the exception of suicide, the how and when of our death is entirely outside of our control. Time is simply a system we invented to keep track of that messy bit in between when we arrive screaming and when we depart in silence.
The truth here, is that calling time 'wasted', is simply an indicator that the caller is unsatisfied with the manner in which the caller has spent the caller's time, for in reality, at the moment of passing, only the caller knows if the passage was worth it or not.