Common courtesy is an unwritten rule.
As soon as you try to quantify it and make it a written rule it's game over, in my opinion.
This forum isn't a paid subscription; You're owed nothing.
The only reason it exists is because there are people around here with 8000 posts or whatever.
Without those people, this forum would almost exclusively be spambots and 'look-at-me--tell me I'm great--Hurry up--write back NOW!' threads.
The regular members choose to take the time to help people out, and if they choose not to bother based on certain attitudes or demands, then fair enough.
That doesn't need to be a written rule.
You've deleted the original posts, but given that they were thirteen hours and nine hours ago, I guess patience isn't one of your virtues.
I'd have said what Jim said.