You know what I don't get? Why people register at your forum & not do anything... Is not that I haven't notice this, but have you? Ive some forum get like 90.000 members (YES, THAT MANY+) but then there actual forum is un-active as hell... with that many members, you should be getting 100s of post a day... but yet no... so why Sign up?
I think it may be for free stuff etc. Some forums say you need to be a member to gain access to certain sections, or you need to be a member for a week to gain access etc.
I guess, but what if that forum doesn't offer anything... Yet you signed up, but don't anything afterwards
Maybe a friend referred them, or its part of a contest (ie sign up at X forum and you have a chance of winning this prize).
Well, you can always delete them if you don't want them to have an account on your forum - some people just enjoy lurking over posting. What do you think? Do you prefer to delete inactive members on your forum?
Moved to Members and Staff Management. Well there can be many reasons why someone joins, I can list a few hundred. Most join for a reason, either they are interested in the forum itself, or they need something, and when they get it they leave, an example would be downloading something you offer.. or for example in AdminBB's case to advertise their sites. Or probably they joined with a good intention of being active, and then forgot about it. Or they lost interest.
It's most certainly because you need the content of that forum so decide to register for it. I've done this in the past on a game forum to get an update to work on windows 7, and also at phpBB Communities to get one of the KB attachments
Sometimes people sign up and don't do anything else because they might want to see just what all your forum has to offer from a members' point of view before deciding if they want to hang around or not. I know I often do this, especially if I'm not familiar with the site/owner or both.
There's also the possibility that a large number of them are spam bots that automatically register... I can get up to ten of them a day sometimes. :x I just delete them all after a week's time. They go to a special validating thing from an add on I installed anyway so usually it doesn't inflate the member count.
Thats a good point you mention, yea they can be spam bots. Most join and don't do anything, but if you go to their profile you will see a advertisement link, and then you will know its a spambot.