Selfishness, stupidity, impatience.

I drove the same stretch of road twice today, and both times a dickhead in a larger than necessary vehicle was aggressively driving behind me, and as soon as a second lane started to open up they zoomed around me. The second one didn't even wait for the dotted lines; he went around as soon as there was enough space.
In both cases they immediately got stuck at the same red light, and in both cases I was about two seconds away from moving into the right turn lane when that opened up. The only result of driving like that was raising their own stress levels (and mine a tiny bit.)

Yeah, but then I couldn't get to the next red light half a second faster...

Why be safe when you can cross all lanes on the highway last minute before your exit

Personal automobiles inherently encourage selfishness and drives to view everyone else as their opponent.

Its simply how cars and driving and every driver is.

That last tip could say “Ensure you have /your/ head checked”. That could help…

Completely agree. Some people refuse to recognize and accept that sometimes the speed of the road based on traffic conditions is slower than they'd like to travel and start cutting right and left to get a few yards ahead.

Car brain conditions a certain kind of mindset in people.

Related too, the people who think that "passing lane" means a Mass Effect FTL corridor where rules don't apply. Yes, there's a person passing ahead. Just because they're going the (verified) speed limit, doesn't mean you get to tailgate and try to bully them. They're still passing, after all.

I've had less of those lately, and more who drive under the limit by 20km. Back streets near home, 30kph. Main road with a 60 limit.... 40kph.

Why. WHY.