Old and slow and in the way. That's all it takes around LA.
My ride yesterday was 38 miles and 1800 feet of climbing up to 12%. I went out a road that terrifies most riders. It doesn't bother me because although there are fast speeds and trees blocking the view the site lines are long enough that drivers can see you from a reasonably long way away.
The shoulder was unusable because of the mudslides leaving gravel covering them. But the traffic was extremely polite to me being in the right of the traffic lane except for one horse's ass. And a couple of people that desperately need driving lessons. When you are going to turn left across a divided road there is no need to pull all the way to the right across the bike lane and into the right side parking lane to turn left. And there's equally no need to wait for a bicycle to cross before exiting a driveway when the bicycle is the only traffic and it's more than a block away.