That is not true, can you tell me why do you think that signature campaining is the easiest way to earn?
I have found out that many people claim the same thing, but it is not like that. I have always thought that signature campainings are usually not fair because new people pretty much spam the forum for some profits, there are even some campainings where  you can join with newbie account!

The requirement that should be most important is that you need to do constructive, quality posts to get payed but let's be serious: campaining managers are not checking every single post if it is topic-related etc. Without decent knowledge it should not be possible to make money on that, because some participants here are just giving useless answers and they are getting payed for that!