Some conditions won't support a meaningful, safe conversation.
If you're not a team (no shared purpose or context).
When the conversation can't go anywhere (e.g. last thing on a Friday, right before holidays).
When overused, it can lose novelty or feel overwhelming.
When the topic is purely mechanical or technical in nature.
In a physical space that makes it difficult to openly share.
When you don't have the majority of the team present.
In chaotic, fire-fighting moments.