be one's upper/ go to pot

「read the Telegraph; vote Tory - 田邉祐司ゼミ 常時英心：言葉の森から」で扱った記事のfollow-upです。

赤字で示したbe one’s upperとgo to potはどんな意味でしょうか？まず、be one’s upperは古いイングランドの表現で「貧乏な」「ひどく貧乏して」という意味です。LDOCEでは、“to have very little money”と定義してあります。

さらにgo to potは、略式の英語で、『ジーニアス英和辞典』によれば「〈場所・組織などが〉（かまう人がいなくなったために）だめになる、堕落する」とあります。LDOCEでは、“if something such as a place or an organisation goes to pot, it becomes much worse or fails because no one is taking care of it”と定義されています。なぜpotかと言えば、potとは「比較的底の深いビンや壺」などを指すため、potの中に入ってしまったら自分の力でも抜け出せないからだと考えられます。

以前、Kate Foxの書籍で、upper/ upper middle classの人々は婉曲な表現を嫌い直接的な表現を好む、婉曲的な表現はnon-Uが好む表現と同時にnon-Uの象徴であると知ったことがあります。もしかしたら、今回の婉曲な表現もその一環であるのかもしれません。(Othello)

Across the barricades: love over the class divide | Life and style | The Guardian

When Emily introduced her parents to his – at the smart Islington restaurant Granita – that went quite well. "The worst was the wedding. My parents were sending out invitations, but they were on their uppers because their business had gone to pot. So they weren't paying, but because they're quite proud, I wanted them to feel like they were still the hosts. The invitations had to come from them. And there were all these titles, and they'd been told his aged aunt would only open invitations that were correctly addressed. My mum was very much, 'They'll just have to take us as they find us.' But my dad was going, 'No, no, no, it's got to be right.' He was shitting himself that somehow he would make some terrible faux pas and our lowly beginnings would be revealed.