Origami folders talk about “collapse” — that moment when many creases fold at once and a piece of paper knots itself into a compact form. The moment just before collapse is tense (the paper wants to be either fully flat or fully folded, not anywhere in between); the moment just after a successful collapse is one of relief.
The tension is multiplied by the fact that all the creases have to be put in place before this collapse can happen. This process of putting in all the creases can be long and tedious. Depending on the complexity of the origami, it can take hours, days, or even months. (Robert Lang once related a story about a particular object he had spent many years folding.)
This is Chris Palmer performing a collapse (from the excellent documentary Between the Folds by Vanessa Gould).
See, the thing about collapse is that it can go very, very awry. The paper is not obligated to fall into the desired configuration. The paper can crumple into something ugly. And spurious creases are (nearly) impossible to undo. A crease in a piece of paper is persistent; an undesired crease cannot simply be removed. So imagine, if you will, spending months (or years) folding a piece of paper, to have your work ruined by an unfortunate collapse.
Defending my PhD dissertation felt like a moment of collapse. All these years of work, all these individual pieces built up bit by tiny bit, all culminating in this one act of bringing together, of knotting together, of collapse. I’m glad to say that the collapse was a successful one. The facets fell in place exactly where I needed them to, and I passed.
Of course, the analogy is not perfect. One can recover from an imperfect PhD defense, salvage useful bits of work, add missing pieces, and try again. An imperfect origami collapse, on the other hand, is difficult, if not impossible, to recover from. The folder must go back to a flat pristine new sheet of paper.