I found that many conferences strictly limit their submission and camera-ready LNCS page to 12 pages, such as source1, source2, and source3 (without the possibility of extension) whereas some offers extension with an additional fee, such as source4. However, the Springer website recommends 12 pages as the minimum instead of the maximum for a full paper.
My questions are:
From the perspective of the conference organizer's side (not the authors of the papers), what are their considerations for this limit, and why are they so strict with it? Is this something like a signed contract from Springer to the particular conference organizers, and they must strictly follow it?
What happens if they let some papers exceed the 12-page limit? Is there any penalty from the publisher (Springer)?