A dovetail joint works because the pins and tails are cut at opposing angles. Pull the drawer front and the joint tightens against itself. No fastener, no bracket, nothing to loosen.
A machine cuts them uniformly, which sounds like an advantage. Uniform means the fit is set by the jig rather than by the wood in front of you, and the gaps are filled with glue. Glue is the weakest thing in the assembly and it is the first thing to fail.
Cut by hand, each tail is marked from its own pin and pared to fit that one socket. The joint goes together dry, under hand pressure, and holds before any glue is introduced.
You open a nightstand drawer perhaps four thousand times. That is what the forty minutes is for. You will only ever notice the difference once, in about thirty years, when the drawer still runs true.
