Why do polls have so many "undecides"?

[ProgressiveModerate]

Looking at RCP average, back in 2020 at this time the average was 50-45 with only 5% undecided. However, today the average is 47-45 with 9% undecided. The number of undecides has nearly doubled, and this isn't just being picky about a moment in time, it's a theme that holds going back months and also looking at state polls as well.

Are there genuinely more undecides? Are people answering "undecided" just as a form of protest, even if they've made up their mind? Have pollsters changed methodology?

[The Economy is Getting Worse]

In 2020, Biden had a 52% favorability rating. Right now, he is under 40%. Both candidates are unpopular now, which is increasing people who aren't picking either for now.

[Birdish]

A lot of soft Biden support who are in fact so soft, they're not supporting him xP

[mileslunn]

Lots who dislike both candidates.  Both have approval ratings at best in low 40s. 

[Redban]

Both candidates are unpopular, RFK Jr has more name recognition and favorability than 3rd parties in other years, and there is a snowball effect - 2016, 2020*, and 2024 would mean 3 straight elections where people don't like the candidates, and the allure of a protest vote or third-party choice grows as people repeatedly are asked to choose between two poor options

(* In 2020, Biden had very good favorables, but I think hindsight makes people look back negatively at the 2020 matchup; they probably see Biden vs Trump 2020 the same as Hillary vs Trump 2016 when they recollect on that election)

[7,052,770]

Millions of people who will ultimately vote for Joe Biden to stop Trump are currently in denial about it.

[Mr.Bakari-Sellers]

Because many undecided are college age, educated whites 18/29  who. Might vote Provisionally I am a Eday judge and most college educated whites identify as Libertarian, closer to RFK but since Eday is between Trump and Biden the provisions ballots will go 2/1 to Biden

That's why a TX or AZ that has Cruz up 2 or Lake can tip D in a close eDays because of provision ballot . I had a Dream yesterday we won TX and AZ on provisions ballots. That's why R nut maps are wrong they don't account for provisions ballots. As an Eday judge almost all provisions go D not R just the military ballots at the end make they are mixed in makes them more R, they account for abstintee ballots

That's why S019 has Biden losing ME and PA is wrong Casey and Angus King are gonna help win even ME 2 in NOVEMBER

My cuz in TX said they are ready for Allred and break Filibuster and Reparations

[President Johnson]

Probably because a decent junk of the electorate is not thrilled about a rematch.

[Mr.Bakari-Sellers]

Probably because a decent junk of the electorate is not thrilled about a rematch.

They are thrilled it's only a select few taking these polls that's unreliable, some voters don't take computerized polls, you will easily see Biden get reelected

[Crumpets]

1) Genuinely lots of people who aren't paying attention or who just don't think it'll be Trump vs. Biden somehow
2) People who are more or less decided but fancy themselves the kind of person who truly weighs the totality of the campaign and are waiting for the candidates to "discuss the issues" and "put forth their ideas" and such.

[Mr. Third-Wayist]

Low appetite for a rematch

[Progressive Pessimist]

Because Americans love being coy about elections, and many make up their minds at the last minute.

It's why we shouldn't necessarily freak out about polls yet.

[kwabbit]

There's obviously going to be high third-party vote this election. Dissatisfaction with the candidates is higher than 2016 and RFK Jr. is polling higher. If the total third-party vote is 7%, then the amount of undecideds is lower. A 47-42 Trump poll like NBC had doesn't have that many undecided really in such a scenario. We'll see how much the third-party vote collapses, but it's very unlikely for Trump and Biden to get the usual 98% between them.

[SnowLabrador]

Because there are lots of shy Trump voters who don't want to look racist.