I think there are so many things that are taken as granted and therefore omitted in the communication. This makes it more difficult to communicate as the personal experience of the participants diverges. Sometimes a wide gap will cause awareness, and therefore exposition of some of the normally unspoken components.

I see the same thing with "common sense". People assume everyone knows these things, hence the label. However the knowledge under that label is actually the accumulation of many small lessons, any number of which might have been skipped by any individual. Especially today, as more and more people are raised by screens instead of parents and community, people can end up with glaring gaps in their accumulated knowledge.