Yes, but where reliability is concerned, a continuum is a problem. You can't say with any certainty where any given thing is on the continuum, or even define its bounds.

This is exactly what makes estimates categorically unreliable. The ones that aren't accurate will surprise you and mess things up.

In that sense, it does compress to being binary. To have a whole organisation work on the premise that estimates are reliable, they all have to be, at least within some pretty tight error bound (a small number of inaccuracies can be absorbed, but at some point the premise becomes de facto negated by inaccuracies).