Ok, so in an attempt to get as high a star rating as I possibly could with all my coaches I set about recruiting.
Using the Search --> Staff feature, and then using a filter to get the right stats I found a coach that I could afford and had a 6 star rating.
After a few weeks I recruited some more staff for different training types and then I noticed that he'd gone down to a 4 star rating.
That's when I realised that he'd gone from 17 defending to 14...
Is this normal? Do coaches stats change depending on age or is this a bug?
Coaching Stats Diminishing 
Linear Mode
