Why is Instant Runoff Voting the worst possible voting method?
This page is a good explainer of IRV's weaknesses and shows some of the alternatives: https://ncase.me/ballot/
Since you mention it, let me offer a candidate for "worst possible voting method (that has actually been used in a democracy)", namely "plurality-At-Large".[0]
It basically takes the worst properties of FPTP and extends them to an entire governing body, allowing a party with less than 50% support to win 100% of the seats (by design).
Fortunately it has been mostly abandoned in the US thanks to the Voting Rights Act and subsequent SCOTUS decisions.
[0] https://www.nonprofitvote.org/the-bias-of-at-large-elections...
A close variant (vote for up to N, top N win, at large) is used in a lot of local elections still; all multimember district methods are banned in House elections specifically to prevent plurality at large from being used there. (Though the Senate uses temporally-segregated two-seat plurality at large in every state.)
Correction: it uses either that or similarly segregated majority/runoff, varying by state.
Majority/runoff and plurality are similar FPTP variants, but majority/runoff is slightly less bad.
The problem with IRV is that you can have a candidate who is everyone's second choice, but then loses out on the first ballot because too few people ranked them first.
Would screening for a condorcet winner (beats all winner) FIRST then proceeding to RCV address this concern sufficiently?
Ballot completion would remain unchanged.
Wikipedia has an example:
https://en.wikipedia.org/wiki/Monotonicity_criterion#Instant...
I think first-past-the-post and IRV are both bad voting systems that are unsuitable for real-world use in elections with more than 2 candidates. Approval voting is simpler than IRV and (as far as I know) it isn't worse than FPTP in any way, so I think we should push for that.
FPTP might be better than approval voting, because approval voting favors weak moderate candidates with no agenda.
With FPTP the people alternate lefts and rights and the system develops. With moderate candidates the system may stop progressing: no reforms, no bugfixes.
The way I look at is that it's a kind of relief valve. If both major parties (assuming there are two, maybe there'll be more...) nominate not-so-great candidates, then the voters have an option to elect someone like Tom Hanks. I mean, I would have voted for Tom Hank in 2016 if I had an approval voting ballot and he was one of the options.
No voting public prefers other candidates, and moderate candidate as backup.
I give you an example I posted in another thread:
* 60% want a dem candidate to win
* 40% want a rep candidate to win
* 70% are willing to join strategic voting to avoid allowing other party to win
In this case, the dem candidate looks like a correct winner.
With ranked choice the the dem candidate would win.
But with approval voting strategic "moderate" candidate wins. If they are moderate, that's good. But they can easily be just weak nobody.
It is not exactly what voting public prefers. That choice is a fake choice, like a girl, do you want to go to bed or be thrown into a forest with angry wolves.
> if there's no particularly compelling reason for people to want that person to be president.
The reason is to not let opposing party win. Strategic voting.
> If both major parties (assuming there are two, maybe there'll be more...) nominate not-so-great candidates, then the voters have an option to elect someone like Tom Hanks.
And they will if it is some form of ranked choice, but not just approval.
In approval voting, strategic voting for moderate/novelty candidates is like this (assuming you have a favorite and least favorite major party candidate and the novelty candidate is somewhere in the middle): you can vote for the novelty candidate if you want. Doing so might cause your favorite major-party candidate to lose if you happen to be the tie-breaking vote. Or it might cause your least-favorite major party candidate to lose to the novelty candidate. You can decide whether the prospect of having your favorite candidate lose to the novelty candidate is worse than the prospect of having your least favorite major party candidate lose to the novelty candidate and vote accordingly. In all cases, if you vote for your favorite candidate you're always helping them win, and if you vote for the novelty candidate you're always helping them win.
How strategic voting works for RCV is that you can put your favorite major party candidate first, the novelty candidate second, and the least favorite candidate last. You know that putting the novelty candidate in the middle won't harm your favorite candidate's chances of winning, since that's a property of RCV (later no harm). However, what you don't know is whether putting your favorite candidate first will help or harm your favorite candidate, and you don't know whether putting the novelty candidate second will help or harm the novelty candidate. Maybe putting your first choice second or third will cause them to win. Maybe putting the novelty candidate first will cause your favorite candidate to win against your least favorite candidate.
This is complicated and hard to reason about, unless you have detailed information about how other people are going to vote. Which seems to imply that such a system would tend to disempower individual voters and empower whoever has access to detailed information about the intentions of the voting public: campaigns that can afford internal polling, Facebook, Google, etc..