Ah, this brought back "fond" memories of trying to reverse engineer a 3-way chat in Teams, and trying to figure out why I didn't understand the conversation. It turned out that Teams would have a kind of eventual consistency for messages, where one or two lines would arrive a few hours later, and pop into existence in the middle of a conversation (three pages up), without notifying you that something had happened. Because, presumably, you had already read messages with a later creation date...
Granted, this was pretty rare, but we noticed it happening at least 2-3 times in a 6 month period. In those cases it caused enough of a headache that I had to start worrying about whether I was seeing the entire discussion, which is a wonderful property to have in a chat tool.
Just wait until you've been forced by your company to use Teams instead, then you'll find yourself advocating for Slack even if you hate it too.