Why do psychologists conduct experiments?
Psychology is an applied science. Most clinical psychology programs have a scientist-practitioner model. Graduates of these programs learn research skills and counseling skills. Like any science field, if questions are not asked, hypothesise are not made, and research is not conducted, nothing is learned and the field is stagnant. The same holds true for clinical psychology. To validate the field and to help clinicians treat mental health illnesses with empirically validated treatments research must be conducted. Hundreds of years ago people with pschizophrenia were thought to be possessed by demonic spirits, analysis used to be the only form of talk therapy, now we have behavioral therapy, CBT, DBT, existential, humanistic, ACT, cognitive, mindfulness, and the list goes on. Ultimately, research helps to legitimize the field and help those we are trying to help.