Relationships between two high sensation-seeking individuals may lack stability, and relationships between two high serotonin individuals may lack dynamic tension.

“You could actually imagine, for instance, that two people of this high sensation seeking, novelty seeking could have a terrifically exciting relationship, but that it actually might be a relationship in which the financial stability isn't quite there, or in which the basic stability isn't there. You could imagine, for instance, a situation in which a relationship between two people of what she called the high serotonin preference would have a relationship that was actually dull, in which both of them found themselves bored at some point, or in which there wasn't enough of the dynamic tension that sometimes is required in order to keep this cycle of desire, love, and attachment going.”