It's worth noting that some people specifically see verbal communication's undocumented-by-default nature as a feature.
When I was younger I found that idea very offensive. I considered people who held that viewpoint to be suspect (engaging in political machinations, or using fluid recollections of conversations to their advantage). I still think there's a grain of truth to my suspicions, but I've learned to recognize that there are acceptable reasons for undocumented conversations.
There's still phone calls. Any co-worker you trust enough to have an "off the record" conversation with wouldn't turn down a "hey, can I call you?" request. They might think it's weird at first, but would understand later I'm sure.
I've called coworkers literally just to rant to someone before. Sometimes, you need to complain, but having a record of that is not helpful in any way.
> I've learned to recognize that there are acceptable reasons for undocumented conversations.
It seems bizarre to me that one could think otherwise. Unless you meant but did not specify that you're only speaking of line-of-business workplace communication, of course. Otherwise, I find it hard to believe you could forge any actual relationships with people if you try to have a record for everything.
I do mean in a business context. I still feel like a lot of business value fails to be captured when important decisions are made in an undocumented medium. The context and supporting facts associated with a decision are often just as important as the decision itself.
When I was younger I found that idea very offensive. I considered people who held that viewpoint to be suspect (engaging in political machinations, or using fluid recollections of conversations to their advantage). I still think there's a grain of truth to my suspicions, but I've learned to recognize that there are acceptable reasons for undocumented conversations.