What is the meaning of マジで終わっている?


This sentence is from Murata Sayaka's 『コンビニ人間』.

> それに比べて白羽マジで終わっている。

It is translated "Shihara is such a loser". I understand each word in the
sentence (I think) but do not understand how this becomes what is translated.
Literally: compared to this or to someone else (???) it's finished with taking
him seriously. What am I missing?




I guess 終わってる is some kind of slang. I found [a page that defines
it](https://www22.atwiki.jp/2shiki/pages/89.html):

> ＜語義＞
>
> ①ダメだ。評価するに値しない。
>
> ②嫌だ、嫌悪感を感じる。
>
> ＜経緯＞
>
>
> おそらく「改善の見込みが無い」「これ以上進展は望めない」→「これ以降何も無い」→「終わっている」。もともと「終わり」「お終い」という語にも、「悲劇的な結末」「改善の余地無し」「絶望的」の意で用いる用法はある。「ああ、何もかもオワリだ！」「もうオシマイだ！」
> この様な意味の拡大から下記Wikiのような意味が生まれたと思われ、。
>
> ＜使用場面＞
>
> 程度が酷すぎて改善も見込めないものを見たときに。

So 終わってる has a negative meaning. It means that there is no hope of
improvement. I guess you could translate it to "a lost cause". In your case,
the translator decided to use "loser".

I found another similar usage
[here](http://nakayoshitwins.hatenablog.com/entry/2017/05/13/FUCK%E3%82%92%E4%BD%BF%E3%81%86%E3%81%A8%E4%BC%9A%E8%A9%B1%E3%81%8C%E7%9B%9B%E3%82%8A%E4%B8%8A%E3%81%8C%E3%82%8B%EF%BC%81%EF%BC%9F%E3%80%90%E8%8B%B1%E8%AA%9E/%E3%82%B9%E3%83%A9%E3%83%B3%E3%82%B0/)
that might help:

> Fuck my life!
>
> = 俺の人生マジで終わってるわ！

The マジで means "seriously" in the sense of "he's seriously a lost cause" or
"seriously he's a lost cause" or something. It just emphasizes the
exasperation of the speaker, it doesn't necessarily literally mean that
somebody is serious or not. In your case, the translator decided to say "such
a" instead of "seriously".

So, considering the whole sentence, we could translate it like:

> それに比べて白羽マジで終わっている。
>
> Compared to that, Shihara is seriously a lost cause.

More context is needed to know what "that" is.

