Another way of understanding this is by saying "so why there is a further level of experience and not a single, eternal one" (like what happens with level 10s), basically the Pliocene Mission has new challenges to the soldiers, engineers, mechanics and scientists. Therefore once they start getting used to these challenges and they acquire more knowledge, it's more difficult to reach the next level because there are a lot of things that the character already knows and the challenges seem to be generally the same.
Anyways, these are all product of my logic and imagination. If you think there's something wrong or there's space to improve let me know.
Thanks!
Gwren1 out!
