I've lived in several states of this fine country. Everyone likes to think drivers in their state are the worst, and it's super trendy to hate on "bad drivers" kind of like hating on banks.
At the risk of sounding like a cliché, I'm adding my two cents.
Don't take this as "the sky is falling"; it's just a few observations.
1. Lots of Mandurah drivers are super friendly.
Sometimes it feels like driving in a country town. People let you in. People give way. People smile. It's really nice, and makes you want to pass the niceness on.
2. Some people are just in too much of a rush.
As someone who has to report on crash deaths so often, I've grown to become a very cautious driver. So often when I'm at a roundabout making sure the oncoming traffic are actually going to follow the rules, I'll get honked by some impatient monkey who can't believe I'm not in a rush like they are. Maybe they're from Perth. Maybe their meth is wearing off and each second feels like an hour. Either way, chill out people. Get home in one piece.
3. People speed.
A lot. No idea what the reason for it is. But if the limit is 70 and you're doing 70, you're going to get overtaken a whole lot.
4. Nobody knows how to use indicators at the roundabouts.
I thought I'd chuck this one in. But honestly, it's statewide, not exclusive to Mandurah.
Every time I see that white Tesla (whoever you are call me, I'd love a test drive) getting around Mandurah I'm reminded that the current madness we live in where random humans operate machines travelling at 110+ km/h will one day pass, and we'll all get to commute safely in electric computer-controlled carriages.
But until that day, please take care on the roads people.