The root cause is the instinctive shake/flick. This is what causes the rogue spot on the scrubs much of the time, I think. What you need is the tug. Kind of like squeezing toothpaste out of a tube. You have the express the last tenacious drop while restraining from flicking it.
I now have a whole routine ingrained in my pee behavior that starts whenever I loosen the tie on a pair of scrubs - drain the lizard, perform the tug, then gingerly fold up, around, and into the boxers and scrubs before tying and checking for the rogue pee spot, which can still persist despite the meticulous hose maneuvers. If the spot is there, sometimes you can just rub it hard against your leg, until the friction makes it hot, and it'll usually disappear soon.
The fact that none of us really noticed the pee spot until we started regularly wearing scrubs makes me wonder how often we walk around with clinically silent pee spots. Those Dockers have a dirty secret...