To understand the role of psi, it is best to view psi as an ability, or feature, in which is bound to an individual human being as a function of his or her personality in the broadest sense of that term.
Much effort has be given in regards to speculating on how psi works, which is not the same as the consideration of what psi is for or why human beings possess such an ability. Such questions must be addressed to move forward in an understanding of psi, and this understanding must be applied to move forward in developing a model of psi.
Psi ability is viewed as the product of evolution, of the same processes of natural selection that has yielded human beings all other features and abilities.
Darwinian Theory has a base explanation for any ability: it serves to help human beings survive and pass on their genes to the next generation. The base explanation here is survival in the biological sense (i.e. the survival of the gene rather than the being).
Psi is assumed to be need-serving, and these needs are significant as they contribute to the health and well-being of the individual so as to make the individual better able, and more likely to reproduce to ensure the passing of genes.
One may take the term “survival” to assume psi is only useful in a critical moment collective with a critical need, but the term “survival” should be understood to mean more plainly: the ability to endure on a daily basis, to withstand hardships and stress (i.e. to be well).
Considerations include the implication that the individuals subconscious will know, typically subconsciously, in what circumstances psi may or may not be needed.
Again, this is not to assume psi can only be used in critical situations or that any event in which can be attributed to the application of psi must have a need behind it, but this does seem to be the case.
(Adapted from the book series “A Quantum Approach” by Dr. Theresa M. Kelly.)