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5 * Staff?

Don't worry about them not being 5 star. In my experience, providing they are the same level as your team (in this case L13) a 4.5 and 5 star staff member will perform the same.

Thank you Paulo for pointing this out, I need to do a few more tests.

My opinion was that providing they're the same level as your team there is no difference between 4.5 and 5 stars. If they're 4.5 star but a level below your team then yes, they don't perform quite so well. This is definitely true for CDs, I assumed it also held good for TDs.

A 5 star will always be the same level as your team but a 4.5 star can be either the same level or one level lower. This is why I always recommend that you not only look at their star rating but also look at their level.

Wait until you get to L20, 5 star staff are as rare as rocking horse sh*t.

Just to add to the confusion, the exception that proves the rule, some L19 CDs display a full 5 stars to L20 Managers. So you can actually have a staff member that is 5 stars but one level below your team level.

But in answer to your question, I don't know why 5 star staff are so rare but as I said, don't get too hung up on star rating, just make sure they're the same level as your team and you'll be fine.