Which is NOT mentioned as the reason why women are poor at public speaking?

While nearly all men are poor at public speaking, women are even worse. This is partly because women cannot tell jokes, but also because we are better at self-awareness and therefore know that our speech is average and the audience would rather be doing something else—(17) thoughts that do little to enhance performance. (18) To combat fear and innate hopelessness, I try quite hard to be better. Every time a book about public speaking arrives on my desk, I skim it for tips. Mostly they tell you to "relax" and to "be yourself"—(19)which is downright irresponsible. This works only for the one in a billion who is born a brilliant speaker. Being good, for everyone else means reaching such an elevated level of nervousness and artifice that you can present an entirely convincing picture of authenticity and relaxation. I have only come across two bits of helpful advice. The first is practice, practice, practice. This is a bore because it takes a lot of time, but there is no way round it. (20)The second is to junk all aids-PowerPoint is a crutch. It is an ugly thing in itself and must be thrown away if you want to talk smoothly. Equally, you must never read a speech. Write it, learn it and then leave it at home, speaking with minimal notes.