The essence of this theory lies in the middle word, Reward. It says that people are likely to fall in love with someone whose behaviour would be rewarding, i.e., beneficial for them.
According to the evolutionary theory, love serves to entice and hold onto a partner in order to procreate and then take care of the progeny that results. In other words, successful reproduction is our ultimate aim, and the romantic love we feel is only a tool to help us get there.
The attachment theory of love states that the type of attachment style one develops through their childhood relationship with their caregiver plays a role in one`s relationships in adulthood.
The Finkel and Eastwick suggest instrumentality theory in place of the helpful but rather constrained reward, evolutionary, and attachment theories. They contend that people are driven to accomplish a variety of objectives in life, including having confidence in oneself, beginning a family, and feeling safe and secure