Being that the Universe is vibrational in nature, your emotions too are thus also vibrational in nature. Therefore, as you experience an emotion, you are really only experiencing a vibration. The state of your present reality is also of a vibration, and as you experience reality in the present moment, you are really only experiencing a vibration that matches the nature of your present reality. Such perceptions do not produce strong emotions on average, because they are of a frequency that matches the present state of your reality which in turn matches your personal vibration. Ergo, strong emotions indicate you are being exposed to a vibration that differs in frequency from the state of your present reality. Such exposure indicates your vibration is in the process of changing since it will alter the frequency of your personal vibration. In this way, you are only making a difference in terms of changing the nature of your reality whenever you are experiencing strong emotions. The stronger are the emotions being experienced, the greater is the change being effected upon your reality since such emotions indicate your personal vibration is changing to a greater extent and the state of your reality must always match the state of your personal vibration.
Since the process of manifesting your desires is actually the process of changing the nature of your reality to better match the vibrations of your desires, you are thus only moving towards their manifestation whenever you are experiencing positive emotions while thinking about them since the presence of positive emotions indicates the desirability of your reality is changing for the better. The stronger are the positive emotions experienced while thinking about your desires, the faster is the rate at which you are moving towards their ultimate manifestation since such strong positive emotions indicate your vibration is changing for the better to a more significant degree than it would be were you experiencing less significant emotions. Thus, the ultimate goal of manifesting is to focus upon your desires while feeling the strongest positive emotions possible. By doing so, you will then be manifesting your desires at the fastest rate possible by changing your personal vibration to match their unique frequency at the fastest possible rate.