What are some reasons a doctor would decline doing work on you?

[Bella123456]

I had been in talks with a clinic (I won't say who as I don't want to give them bad rep) but after going over pictures, details, health records, etc. - I was declined!!!

I got an e-mail this morning telling me that the clinic had to cancel my appointment and decline the operation due to "risk" and they did not state what the risk was. I did reply but I am not sure if they will reply back or not. I am not sure what the hours are over there, I just know I read the e-mail earlier this morning.

What are some reasons a doctor would decline doing work on you? I am at a loss here!