When you see video of a rocket launch, you hear them talk about “max q.” This is the point where the rocket is under the maximum amount of dynamic pressure from the atmosphere.

As the rocket accelerates, the pressure from pushing through the atmosphere increases. Eventually, though, the atmosphere thins, and the pressure reduces. There’s a crossover point where the pressure is highest: max q.

Similarly, when you’re doing a jigsaw puzzle at home over the holidays, the puzzle process has a max q.

The difficultly of a puzzle decreases with each piece you place, as fewer options are left for the remaining pieces.

However, the difficulty of placing a piece increases as you run out of easy and obvious placements.

There’s a crossover point somewhere in the middle where a puzzle is at its most difficult. There are still lots of pieces and positions left, and the easy placements have run out. This is puzzle max q.