One of the worst looks for a mediation counsel is when the capacity for independent thought is lost. I see it only occasionally.
This could be because the client is a bully or counsel is working from a position of greed or lack of experience.
My own view is that when it does happen, it's usually because the lawyer is lazy and has failed to manage the client's expectations as the case has matured from filing to mediation.
Occasionally, it's because they don't want to lose the business, but I think that's the exception.
Anyway, doesn't really matter why, it always ends badly.
Much of personal injury lawyer John Day's advice in his 12 part think piece on What it takes to be a great trial lawyer is relevant here, especially these sections;
1. Great trial lawyers don’t cheat
2. They have the ability and willingness to undertake (and share with the client) a cost-benefit analysis throughout the litigation
3. They can pull the trigger
4. They are willing to be themselves
5. They have the courage to tell the client the truth
See also Greedy lawyers blamed for lack of mediation