Desire is the single most powerful factor affecting the outcome of your life. The more desire that is present for a particular experience, the more likely it becomes that you will manifest that particular experience.
The amount of desire you have for a particular experience also indicates the degree to which that experience will play a role in your life. The more desire you have for an experience, the more willing you will be to think in a way that makes you feel as if your desires have already been fulfilled in order to experience their fulfillment.
Since the only way you can truly ever experience anything is through the imagining and feeling as if it is a reality for you right now, the more willing you are to give your attention to that which you want as if it is already a reality for you, the faster you will align with that experience and manifest it.
For this reason, if any desire is present for a particular experience, you will likely give your attention to that experience through your thoughts to a certain extent. If there is a substantial amount of desire for an experience though, you will be willing to give a substantial amount of your attention to thoughts of that experience being your present reality and this will result in its manifestation.