It depends on what type of psychologist you're working with. Behaviorists and cognitive-behaviorists are entirely about data. Psychodynamic schools think data is useful but can't be accurate (unless it agrees with them). Humanists think data is suspect because phenomenology is nearly impossible to quantify.
Behaviorists say that phenomenology has no place in psychology BECAUSE it can't be quantified. Humanists say that if you remove it from the study of psychology, you're not even studying psychology anymore. Psychodynamists say this is all the result of deep-seated desires to fuck our mothers.
It's super political. Like, even within Psychology departments there's vicious divisions. We have two professors -- a clinical psychologist and a religions psychologist -- who you're very careful to bring up in the other's class. Religions psychologist believes that mental disorders are an arbitrary assumption we make about others and that labeling them as abnormal and treating them like they're defective is cruel (the Zsasz theory). Clinical psychologist obviously believes the opposite, and that refusing to provide them care is cruel. Shit gets real when you mix in the suffering of others. It's a Cold War only because they both have tenure, but in many cases that hasn't been true. Psychologists will at times launch all out war on each other, if they even talk to each other. At our state psychology conference, the psychodynamists have their own conference in the same city over the same weekend, but have separate events and attendees.
It can even get bizarre. My department head -- an I/O psychologist -- walked into my Abnormal Psychology class once and made a joke about he didn't have to take a class on crazy people.
Nature vs nurture, behavior vs thought, unconscious vs subconscious/preconscious, etc. Every science has their factions, but psychology's factions are intense because they aren't just basic disagreements about whose subject is more important, but basic disagreements on the nature of facts. They're philosophical differences (that word again). For example, my basic assumption is that humans are driven by an innate desire to grow and continue living. A behaviorist's basic assumption is that humans are catalogs of their learned behaviors. I assume that our desire to grow shapes our behavior, while a behaviorist would say that learned behaviors shape our growth. Psychologists can agree on facts only until you get to the point of application and implication. Then shit hits the fan.