People tend to have so many unfulfilled desires because although they may know what they want they constantly live in their reality of "don't have." Until they can align themselves fully with the vibration of "have" they will also never get what it is that they want. A big part of the difficulty is that society and the world keep telling them that it's hard, there's not enough, and they don't deserve what they want. For many the reality of "don't have" is too big a stumbling block to get past and they can't visualize or align themselves with having what they want.
When people go to a psychic and the psychic says, "I see you having what you want in 6 months," then people can finally align themselves with the idea and vibration of having because the psychic has already seen it as so. This gives them a new vision of what is. A psychic can help to reinforce or redirect a persons focus allowing them to resonate with the vibration of their fulfilled desire. Once they have been brought into alignment with having their wants fulfilled it's much easier for them to actually manifest their desire into reality.