“Argue for your limitations, and sure enough, they’re yours.” Richard Bach
The common saying, “I’m my own worst enemy” comes to mind.
So much of life seems to be a self-fulfilling prophecy. My son cries that he can’t do his homework and that it’s too hard…and the homework takes him hours longer than it usually does (and is supposed to). My friend goes on a job interview, certain that she’s under-qualified and will never get the job…and she doesn’t. My client determines that his upcoming meeting with a difficult colleague will never amount to anything…and it doesn’t.