My T is the first I've chosen myself and he's great, so in a way the answer is zero. But I did have bad experiences in the past.

As a teenager I was sent to this psychologist who just made me do relaxation tapes. This was completely stupid given I was living in an abusive home, was SIing and had just tried to SU. Breathing exercises would just totally solve all my problems.

At uni my friend persuaded me to see a counsellor at the student counselling centre. She was awful, she harangued me to talk straight away and then said she couldn't help me if I didn't talk. I said I didn't want another appointment but she sent my GP a letter claiming I agreed to another one and then didn't turn up. My T says she was probably trying to cover her back because she was such a rubbish counsellor...

When I actually chose someone myself, I got it right first time.