I don't know if they're quite so strict these days, but 20+ years ago they seemed to be absolutely obsessed with you pulling on the hand/parking brake every time you stopped for more than a couple of seconds, at a red light, a pedestrian crossing, or even just at a "Give Way" (Yield) sign while waiting to pull out. It was quite ridiculous, making the task of driving around town far more tiring that it need have been. Of course, once the test is over you can just adopt the normal everyday approach in which the brake is released at the start of your journey and applied at the end!
Wow! So THAT is why DH always did that! I thought it was an odd quirk of his that he always pushed the button in.
That's the way it tends to be taught here, although I've never understood why that's so. Why do they think the ratchet and pawl arrangement exists?
Some people even get quite annoyed if they see somebody pull up the brake without holding the button and start going on about wearing out the mechanism. Of course, if you really wanted to reduce wear-&-tear on it overall, you wouldn't be using the parking brake every ten seconds!
P.S. Try turning up for the test in a vehicle with U.S.-style foot-applied parking brake and automatic vacuum release. That should cause the examiner a few headaches!