My Answer: “Lightening” of the Partzuf indicates the weakening of the screen, not the desire. Desire itself is never taken into account. The presence or absence of the screen determines everything.
Therefore, we only consider the screen. As for the desire, it becomes included in the act as long as there is a screen over it, since without a screen the desire is under restriction. Only the screen determines the degree of similarity to the Creator. It defines the character of the spiritual Partzuf, its magnitude, and height. Hence when we talk about a desire, we mean a desire covered by the screen, not simply a desire.
In our world, a person evaluates everything within his or her desire as well. However, other people are not interested in the desire itself; rather, they want to know how much the desire can be realized. You can’t simply scream, "I want!" You should pay and then you’ll receive.
The Hebrew word for "money" (Kesef) comes from the word "cover," or "screen" (Kisui). In this way, the desire is evaluated according to its screen.
From the 2nd part of the Daily Kabbalah Lesson 4/30/10, Preface to the Wisdom of Kabbalah
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The Preface to the Science of Kabbalah: "The Weakening of the Masach for the Creation of the Partzuf"