What does it mean when an account is closed?

Recently I started playing correspondence and so far I've played against four players whose account closed during our game, or shortly after. I've also seen accounts that were banned because of cheating and those looked different than these. So I was just wondering what it meant.

@TheKingClash said in #2:

An account may be closed if they go to lichess.org/account/close.

Sure, but what are the odds that so many people would close their accounts? Doesn't make much sense to me.

The people who cheat or do similar things that are against the Terms of Service normally only get marked as "This account has violated the Lichess terms of service", normally you can see this written in their profile.
This may lead to those people closing their accounts to essentially "hide" the fact, that they violated the ToS. But most people closing their accounts aren't players that violated the ToS: Some people may want to play/ post less often and close their account due to this, some may close their account, because they rage quit. And then there are those players, who choose to close their account because they can.
As far as I know, closed accounts can be re-opened (if requested), though users can also contact lichess to delete the account indefenitely, a famous example of a closed account being @ ghost.

You don't imagine how many people like to have multiple accs just to play the same thing. Not to cheat or evade bans (well some do), but just for the sake of it.
I can speak of the crazyhouse variant for example, lately there's been an exponential grow in the number of new accs playing regular tournaments, many being already expert players. It's obvious they're not new players. You can also recognize them by the openings they play.
Last prized tournament I played (a week ago) I played 17/25 accounts created less than a year ago. I'm sure not all, but most have a main account or even more already.

@george_mcgeorge said in #4:

a famous example of a closed account being @ ghost.

I haven't heard about it.

" lately there's been an exponential grow in the number of new accs playing regular tournaments, many being already expert players."

They got to expert miraculously by reading our forum.

"What does it mean when an account is closed?"
It means that the account is not opened. Unopened!

It means they can come on here and ask why their account is closed.

@Fastbond
Major reason is that accounts being closed by Lichess when it finds user guilty of not abiding by Terms of Service especially cheating.