[MrScruff]

Completely disagree. I probably have 3 or 4 of these spontaneous conversations that wouldn’t otherwise happen a day when I’m in the office. It might start with ‘what are you working on’ and branch off from there, it’s not just small talk.

[juve1996]

Or it could be another negative coworker that wastes your time to complain, gossip, or talk about other employees, or criticize other people.

It will be impossible to quantify these "water cooler chats." For as much work gets done, just as much probably doesn't.