Many good answers in this thread (and some stupid ones) but there are a few critical issues that the current British government will not accept.

First, currency. GB does not want to give up control over the pound, and their previous agreement did not force them to adopt the Euro. There are several other EU countries that have not yet adopted the Euro, but all except Denmark are obligated to switch over once certain criteria are met. GB might be able to negotiate that privilege again, but the EU is in a stronger bargaining position now.

Second, immigration. For as much as their country is suffering from their own strict immigration policies, the conservative government is still making political hay out of xenophobia and bigotry. Reopening the borders would be a tacit admission that their rhetoric was bullshit.

Third, taxes. Joining the EU means contributing to the EU, and while their nation may save money overall due to improved trade relations, the conservative government has made the cost of admission another talking point.

Basically, the current government would have to renegotiate readmittance to the EU, and they would get a worse deal than they had before. Doing so would make it obvious that leaving was a mistake, and their government could only be consisered an objective failure. So they won't do it, even if it is the best option available.

The ones who fucked our country don't want to admit they were wrong.

The party that's been in charge of our country has been dismantling and selling everything worthwhile for over a decade, and the only viable alternative party seems to be running on "we don't want to change anything major, but at least we're not those guys" because they're too scared to say anything after their last leader got torn apart constantly by the right-wing press.

I'm honestly worried about what we've become and how everything is just getting worse here. Nobody seems to have any hope for the future anymore, there are no positive things to look forward to, just a constant spiral of rising costs and declining health and public services.

There are a lot of reasons, but I think it boils down to the people in charge do not want the embarrassement of crawling back to the EU.

It would be total ego destruction and that is simply untennable. This is what happens when the right gets enough power to make a change and then has to experience consequences.

Something something leopards and faces.

it's like an unstable ex-girlfriend trying to get back together. and now she's down on her luck with even less to offer.

Britain had a highly favourable agreement with the EU that it negotiated decades ago. If it wanted to rejoin, it would do so without those privileges.

Screw England, let's just let Scotland and Wales join without them

It would be smart, but their pride forbids it. Besides, when re-joining, they would start off like any other member, not as privileged as they were before thanks to Thatchers blackmailing. And they would have to ditch the pound in favor of the Euro, which would be the most painful thing.

But on the long run, they will have to come back. It is not a question of "if" but just "when" if they want to survive, and the longer they take, the more painful it will be.

Sure. There's an application process; supposedly they can apply. It will take years, with a lot of conditions, and none of the previous exemption they had.

Why would the EU accept that? GB needs to make its mind about that. It had so many specific benefits in the EU, and it still left because an idiot gambled the decision in a referendum.

The brexit could have meant the end of the EU. It's not something you can come and go on a whim. So GB needs to pay for its stupid decision, because the stability of the EU depends on it, no country should ever get the idea that leaving the EU is inconsequential.

They made their decision to leave, now they have to deal with the consequences of that decision.

Pride.

It’s like thinking about marrying your ex-wife again, just after you went through an awful divorce, that took years to get accomplished, which you had insisted in. It would make you look somewhat stupid and the question is whether your ex-wife would let you move back in to your former house (i.e. the EU). Who knows…

You wanted it, you got it, now live with it!

My question is if the EU would even want the country back. Would you want to deal with a country that flip-flops that hard?

It's not an on-off relationship.

Assuming the UK could get itself together and find the political willpower to do so...it still won't be easy. The EU has to agree to it, and it would require all members of the EU approving them rejoining.

As I recall, the EU warned them that if they left it would be very challenging for them to rejoin. The idea was to discourage them from leaving the EU in the first place. But they did. And now they have to live with the consequences.

If I'm not mistaken, the pro-Brexit party (they call them Torys) has been in charge. If they want to move in a different direction, they need to vote different people in, which has not been happening very quickly.

Politics is complicated, basically.

I'm not an expert in this topic at all, but there's a few reasons i can see. One major reason is that you'd have to get a big portion of the country to admit that they were totally wrong and got badly scammed, which people (especially that particular portion of people) won't allow themselves to admit.

It won't happen as long as the Conservatives are in power. They've been pushing the Brexit is great agenda for ages and have finally admitted that maybe it's not brilliant, but it's still pretty great mind you.

There is probably going to be an election in January or February of 2024, because of the utterly stupid way that UK politics works there may not be an election, who knows, but if there is an election and ~~if~~ when the conservatives lose and labour win it might be under cards but it's probably going to take years if it does happen.

Hubris.

Others have already mentioned some of the many reasons why.

But i would like to add that even if they'd rejoin, they could not do so with the same conditions that they had before. Since they joined the predecessors of the EU so early, they had a number of privileges that a new joining member nowadays would not be granted. So from that side "going back to how things were before" wouldn't be possible to begin with.

Another factor is that the EU doesn't necesarily want to take the UK back.

The Brexit, and other anti-EU movement in Europe do not come out of nowhere, there is a lot of issue with how the EU works, and some fundamental disagreement between members (and/or political parties within member states) on how should the Europe evolve (Just a big free-trade area, or a continent sized nation with a real political power and geopolitical weight), this is the context behind Macron talking about a Multi speed Europe

A big question is whether we should take new members right now (including Ukraine/Turkey/UK) or deal on the institutional issue and agree in which direction we want to move together rather than taking more people

I always figured it wouldn't be the UK rejoining the EU if that ever happened. But thats putting the likelihood of there no longer being a UK over their re-entry into the EU.

Also they never adopted the Euro so they always had one foot out anyway.