Like intellectual Charlatanry ("sneaky behavior") or physical Abdication, which are vices about "bailing on" someone, not stealing their resources, but dishonoring them, disregarding them, disrespecting them or their actual possessions, it is at the cost of their joint success. Like its reference virtue of Resourcefulness, Fallowness involves cleverness, but means "unsown, or not pregnant." One is not "baking anything up" or growing anything "in their heads." It is a character "vice of deficit of Resourcefulness" in which one's cleverness is used in a "win/lose" or destructive way that disregards, dishonors, and wastes the efforts and resources of the other partner. It is about the deceitfulness of a partner, in using the "art of slacking." You might say that the partner with this vice is a master of "laying landmines," which relies on passive distance for their own, selfish survival needs, instead of the "we-attitude" of Resilience.
In being unjust as a partner at contributing to achieving a goal, the Fallow partner is burdening their mate in collaboration to a goal, being so bent on their personal "survival needs" that they have managed to accomplish nothing more than to grab the last life-preserver on the Titanic. It's all going down anyway.
People comment at the end of the relationship that, "I never knew that his main hobby was as a couch potato," or "the hard-worker I married was nothing but a slacker." That is the Fallowness of a partner in its usual effect - of such weak personal boundaries, filled with boundary holes, that they let all their own ideas and other resources, drain away needlessly, and without reaching their full potential that can only happen when two people are working on a goal. Life cannot be won without the other partner. The Fallow have been called, "a homebody" and "slacker."
The Fallow person uses an Immature Ego Defense, called, "Passive-aggressiveness" to rid themselves of guilt, and a Primitive Ego Defense, called "Denial" to hide from the reality of having responsibilities and duties, both in the relationship, and personally. (The Ego Defenses guide us in finding friends and mates who happen to have similar maturity levels.)
It is pathologically narcissistic (or childish thinking) to be Fallow, a ne'er-do-well, "burnout" or "loser," because we usually want to be its mature version, Resourcefulness, which makes for the "win/win" behavior of teamwork in the face of problem-solving. The survival at hand needs to be that of the couple, not either individual.
The other vice of Resourcefulness as a virtue, is that of moral excess, called, "Artifice" or "deceit,"a "con artist-like" state where a person of good enough basic skill at something, works their way into more duty or responsibility for reaching a goal, leaving the other partner, "out in the cold" or "a fifth wheel" in the face of a challenge to their joint goals. They then, get mislabelled as not "pulling their own weight" or as a "bully" in the relationship. Which leads to destructive results for the relationship.
Someone who is romantically making use of Fallowness is a narcissist, actively wasting resources and taking them away from the achievement of the goals and the dreams of a mate, by trying to secretly preserve their resources.
As a vice which makes partnership within relationships fail to get to goals, Fallowness is intellectually unattractive. We consider dishonest behavior to be negative in many ways, including in sexual attraction, since it actually depletes the reserves of one's own, or the other partner's masculinity or femininity".