Probably many in my life experienced such an annoying problem when the need arose, which is represented using a pencil, but you have neither of which turned out not to mean an inability to draw, and many believe the lack of ability to image. And if you ask for it, you'll probably say – "I can not draw", but if you ask why, you certainly do pronounce banal phrase, "I have no talent, no talent for drawing." Just want to convince you otherwise. It is possible that the first half of this answer is true, but the second is absolutely not true. I assure you that with the right approach to teaching and student desire, any man can be learn to draw, if not worse than any artist. You need only a desire to learn this and a little patience. Of course the level of training will depend on the time spent and individual abilities, which are present in everyone, but they are developed to varying degrees.
None of these people who have no ability to image it. Everyone who has eyes, hands, and brains – and has the ability to image, since it is these components need to start learning, and of course the desire, because if people do not want to learn – it is not possible to teach anything whatsoever, contrary to his wishes. But to become a good artist, that talent is needed, because artist who is able to portray just seen is primarily the ability to create, to create "their own" works of art.