There's a mentality though that goes along with it
The idea of "wasting" a pitch seems to stem from the mentality of "don't miss an 0-2 pitch somewhere the hitter can hit it." In other words, if you were going to miss and not execute the pitch, miss it so badly that they can't hit it hard somewhere because, after all, you still have a few pitches to play with.
The problem with that mentality is that it seems to give the pitcher and excuse to take a pitch off and "waste" one. Maddux was probably much more focused than that.
Reminds me of the "aim small, miss small" shooter mentality.