Propagation is spotty at best.
QRM is your constant companion. This article will consider these issues from the Net Control's point of view, at a later time will will look at this from the net member's view. Many people report the most enjoyable net operation is before the net ever starts, this is the time for leisurely, enjoyable QSOs. Your helper should be someone who you hear well. That means they will hear the stations too close by for you to hear.