I learnt to drive in another era (early 90s) and I have to agree that lane usage and signalling on roundabouts appears to be completely random.
In the example given, I was taught you should be in the left hand lane and signal left for the first exit. For all other exits, you should be in the right hand lane and signal right UNTIL you’ve passed the exit before you want to turn. You should then signal left and change lanes to take the exit.
Just checked the Highway Code and section 186 does suggest this is still the “right” way to do this, but I think it’s easier said than done (e.g. 4 exits and 3 approach lanes. I would go for the middle lane for the second exit (straight on) and I probably wouldn’t signal).
https://www.highwaycodeuk.co.uk/changes-and-answers/-highway-code-for-roundabouts
Never heard that before, but I like it 👍