Like intellectual Pedantry or physical Tyranny, which are vices about taking over a partner's status at the cost of our own success, "overly optimistic" or "Pollyanna" behavior, or Insouciance is a character "vice of excess of Equanimity" that sees one as being the essence of "win/lose" or destructive. Only in this case, it is about "the blind leading the blind" as if we have resources and power to please or distract a partner, when we really have no assurance of a stable, smooth ride forward. This overconfidence or Hubris regarding the path to our goals, sabotages the whole overall goals of the relationship and therefore the partner. It is not a team approach. It makes the Odysseus, or "father instinct" for freedom and "smooth sailing to a goal that men crave, feel terrible and not the master navigator of paths to success like he likes to be, and makes the Artemis, or "night hunter of success" in women feel misled, and therefore not able to grant a blessing of success on one's path to a goal, which is her instinctual romantic and spiritual right as a woman. Similar to "rose colored glasses" as opposed to mere "negligence," but with the "sabotage" of community resources by the Pollyanna, insouciant person. It is therefore unattractive sexually.
In being unjust as a partner at contributing to achieving a goal, the insouciant, Pollyanna partner is only pretending to have real and true skills of navigation and collaboration to a goal, but is instead utterly wasting the resources of the other partner on a "pipe dream," fake or unattainable. This is misleading the partner into thinking that you are a resourceful and stable person when you are living on wishful thinking, and leads many to comment at the end of the relationship that, "I felt misled and deceived," or "I feel baited and switched," or "what looked like easy success is not what I ended up getting out of you." That is the insouciant Pollyanna's usual effect - through the holes in the boundary allowing wishful thinking to substitute for reality, the illusion of control over the world around us. It is "external locus of control" of the boundary.
The insouciant Pollyanna uses an Immature Ego Defense, called, "Idealization" - which is like "a mirage, where one starts to self-delude into thinking that what's yet to be achieved is already in control," or worse - that what is only a wish is somehow an actual attainable reality. (The Ego Defenses guide us in finding friends and mates who happen to have similar maturity levels.)
It is pathologically narcissistic to be Pollyanna-like, because we usually want to be its mature version, given that insouciance produces destructiveness, and a "win/lose" behavior, while Equanimity, makes for "win/win" behavior in the face of a truly uncertain situation. It is condifence to be sure, empowered by Competence, and the opposite of foolish Hubris with a lack of Observing Ego.
The other vice of Equanimity as a virtue is that of moral deficit, called, "Alarm" or "overwhelm," where a person of basic skill at something "assumes the worst," and lets their anxiety caused by personal boundary holes make them feel overwhelmed and imperiled by even small obstacles. Rocking the boat" terrifies them, inlike the masculine spirit of Odysseus, and the overwhelm and "stress case" of the alarmist takes over the couple's resources (and employing the Defense Mechanism of Undoing, Denial and Repression as their unconscious strategies for avoiding the reality of the challenges to reaching their real goals.) It is like buying tons of insurance for a tiny little, harmless worry, burning money, time, energy and resources.
Someone who is romantically making use of insouciance is a narcissist, wastefully taking resources away from the achievement of goals and the dreams of a mate, by pretending to have Equanimity at a task that actually takes some seriousness that really will lead to success.
As a vice which makes partnership within relationships fail to get to goals, Insouciance is intellectually unattractive, consider cowardly 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"