Every meeting has its unwritten rules. There are rules about how polite you have to be, whether or not peoples formal position in the organizational hierarchy matters in the meeting (“The boss has the last word in the meeting”) or not (“Everybody’s arguments and ideas count”), there are rules about how far you can go off-topic before someone stops you and how long you can talk without beibg interrupted or frowned at, and so on and so forth.
One of the reasons why newcomers often remain silent over the first couple of meetings is that they are careful to learn the unwritten rules before they participate actively. But what if one of those unwritten rules is that everyone should participate actively from the start? 
Anyway, I think we can agree that some unwritten rules work better than others and sone work better for others than oneself.
Which unwritten rules do you find most annoying? Which do you find useful?
And what kind of rules would do you miss in your meetings? How could those be introduced in practice?