Everyone has an agenda.
The more honest and open you are about your own, the more likely you are to find a suitable class.
Do you have health-problems? Have you bad knees? A bad back?
Are you concerned about being thrown on the floor?
Does the prospect of self defence training frighten you?
Is your age an issue?
What are your expectations?
Are you willing to commit to a weekly class?
Do have previous tai chi chuan experience? (Are you hoping that the new class will be the same as the old?)
Are you attending class because you really want to, or because you think you should?