....and it's not just "hold items", but MELs and the combination of MELs that we're being asked to accept on the 767.
You can have 20 hold items, all of which can be fairly benign. You can have 3 MELs which cause you to seriously say "Uh uh. You either fix something, or give us another aeroplane, or we can walk off and go home", or which have such a compounding and significant effect on, say, performance data and/or operational issues that you end up delaying the flight just to figure out exactly how you're going to handle it.