Pseudo-psychology/pseudopsychology, also called "pop" psychology, are schools of thought or self-help programs that are popularized by the media and spokespeople. Sometimes pseudo-psychologies are trends that fade quickly but sometimes they have been considered valid by some people for indefinite amounts of time.
These programs most often tend to be popular for a year or two and then disappear when the next fad program appears. These types of programs appear to work in the short-term, but generally do not produce long-term solutions to personal problems. Pseudo-psychologies are not based on empirical research or held up to scientific research standards. Oftentimes these programs appear to work within the context of seminars and retreats where everyone is working together on the same things and an initial perception of effectiveness takes hold but many times these practices work less well in the real world.
Some recent movements from the last few decades that made a big splash but then retreated into obscurity have been EST, Eckankar, Silva Mind Control, Transcendental Meditation, etc. These schools of thought still exist but are only practiced by a much reduced number of adherents.