Day by day, new members keep registering everyday. Only few of this member find it easy to rank up. Imagine an account opened for more than 2 year that still exist as a newbie. These are some of the reasons I observed why some of these people may find it difficult to rank up:
All the points you highlighted in your post are all valid and could be the reason for non ranking up of low ranked members especially newbies in the forum. I think we have about millions of newbies account in the forum, more than 50% of the total forum members that are still newbies and haven’t ranked up to the next rank yet.
Everyone joins this forum for a reason and if the reasons they are joining the forum is being meant, every other thing won’t matter to them again. As you said that some come for bounties, if that’s their major reason you can’t persuade them to rank up their accounts to get better offer in signature campaigns. They might have valuable informations that could help forum members but if they are here for other reasons that is where their focus will be which I don’t blame them for.
The main thing is to keep the forum clean out of spam, scams and anything illegal. Making sure the rules and regulations guiding the forum are being followed by every member. If that is achievable, the forum will be a better place for all of us.