They have three examples, and all of them ended with the person leaving; it just sounded to me like they were implying that the person leaving represented a failure on their part as a moderator. That, had they moderated better, they could've prevented people leaving.

Each of the examples had something bad happen in the lead-up to the person leaving.

Yes, and? I honestly can't tell what you're getting at here.

That the bad thing they were talking about was the bad stuff leading up to the person leaving.

That was bad yes, but it sounds like they feel that the outcome each time of someone leaving (and possibly with an angry message) was also bad, and indicative that they handled the situation incorrectly.