I have been pondering this on several occasions, but never made it as far as posting before.
On several occasions, I've noticed people join the various channels of OPU, say "Hello" and get no reply. Shortly after they leave, or spam the channel trying to get response, before going away. Often I miss them by a couple of minutes only, and rarely they are seen coming back.. at least in my experience.
In the Download section for IRC is gives a basic description of what IRC is, and why we use it. However, for the untrained user it must seem like we are a inactive bunch, at least if you happen to be a European, logging in during the daytime. Nobody responds within the short time the "visitor", and they simply leave.
So, my thought was, that it perhaps would be useful to include a sentence about the necessity to wait at least 5 minutes for a reply from the channel.. or to include the description of how to call people's attention in IRC (Slap or highlight or any other method I have yet to discover).
Though annoying at times, it might just be that we gather up a bigger crowd ?