This is not a bug report!
I was reading through the documentation, and my attention was caught by the explanation of Motivation. It says that when a player does not travel with her coach, her motivation is reduced 25%. Traveling with an assistant will reduce this malus. I think that I have not previously understood what is meant by 'traveling with the coach'. Most of the time all four of my players go to the same tournaments, and I had assumed that as long as the coach was at that tournament all four players would count as 'traveling with the coach', but I am now thinking that was wrong. Do I need to have three assistants, one for each player (leaving the coach for Emily), or is one enough?
Second, all of my players are making enough money to travel first class and stay in five star hotels. We have just finished the British Open, where Sarah Pitkowski took both the singles and doubles titles. She is at the training center with the coach, and her motivation is listed as 'low', with her bar extending maybe a third of the way across. Emily made it to the third round in singles and lost in the doubles semi-final, and her bar is almost too short to be seen! What in the world does it take to motivate these women?
On the other hand, Tauziat and Demongeot lost in the finals in doubles, going out in the second (Demongeot) and third rounds in singles, and their bars are almost full. There must be something going on here I don't understand. Does it have anything to do with success relative to ranking? I doubt it, since Sarah was ranked 23 in singles before her victory. (She rose to the top 10 for the first time in her career, which also put her on track for me to succeed in her current contract.)