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Yep. Actually the behavior of IRV is extremely unintuitive (despite how nice it sounds). Even using very simple models that assume every voter has political opinions completely described by a 2d political compass, prefers candidates that are closer to them on the compass, and that voters are normally distributed around a central point, you get very strange behavior! Here are some diagrams that illustrate the effect: https://rangevoting.org/IEVS/Pictures.html

interestingly, IRV is not even monotonic! It's easy to construct a situation where converting people to have the same ranking as you causes you to get a candidate you like less. (The concave parts of the voronoi diagrams describe areas where this happens.) If you're curious about this, a few years back some friends and I tried to make a video describing this phenomenon: [0]. (Our editing and presentation skills are nothing to write home about but I think the video is interesting.)

[0]: https://www.youtube.com/watch?v=0m7vtt9jXpM



Here is another, interactive explanation of this phenomenon in IRV, as well as some alternatives that do not suffer this issue: https://ncase.me/ballot/


I don't understand why Ranked is so popular. Range voting is just easier and better in every single way.


> better in every single way.

Range can't satisfy Condorcet (that is, if there is a candidate that would win every head-to-head, that candidate should win the election).

Of course, the most common approaches to RCV also fail that criterion, but it's potentially a way some ranked methods are better than range methods.


> Range can't satisfy Condorcet

That is not necessary a desirable feature. If that is desirable or not depends on your value system of what elections should achieve. What is 'fair' or 'correct' is not universal.


Granted, but it seems a reasonable enough thing to ask for that "better in every single way" deserves qualification.




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