There is a mismatch between the users that coinpiler is looking for and the number of posts they are wanting for people who join the campaign. They are essentially looking for people who, in the past have been very active and posted more then most other users have on average, while they are only asking for 40 constructive posts in order to qualify for a payout (which is very few for a signature campaign).
They assume that people will continue posting at their usual pace, and the 40 constructive posts limit wont matter.
It does happen - my signature campaign has a minimum requirement of 50 posts/month, but I guess I will do twice that.
Writing over the limit is your choice.
