The publishing business and self-help books
The first thing you need to know is that, unlike drugs, self-help trade books (mass market books in local bookstores) are not "tested for effectiveness." These books, even those written by journalists and free lance writers, aren't even reviewed by psychological experts for accuracy, effectiveness, or dangerousness of the ideas. Instead, the publishers seek books that seem likely to sell because the topic is "hot" or the book has an attractive "gimmick." The largest publishers require that writers have a literary agent before they will even consider a manuscript. Thus, it is these agents who really select the books for the big New York publishers. Agents ask "will it sell," not "will it help?" Later, if the book is printed, the publisher's sales representatives have only seconds (maybe a single sentence) to sell a book to big bookstore buyers (there are 50,000 new books every year). By contrast, professional books, like college textbooks or books for psychotherapists, which you won't find in the usual bookstore, are very carefully reviewed by several highly respected professionals (because no teacher would use a textbook with glaring errors). With self-help books (almost all are trade books) the attitude is "let the buyer beware." Selecting a highly advertised "best seller" tells you almost nothing about the scientific quality of the book. In fact, only about half of the so-called "best sellers" are considered good books by mental health professionals (Santrock, Minnett, & Campbell, 1944). Publishing a self-help book is not a highly scientific process.
Next, you need to realize that more than 2,000 self-help books are published each year. So, over the last 25 years more than 20,000 such books (maybe 40-50,000) have been pushed by bookstores. That sounds like a very commendable effort to help you, but the question is: What is the main motivation of many publishers, helping the suffering or making money? No doubt, some care; most are more concerned with making money (yet, supposedly 75% of published books lose money). Many new books merely repeat what has already been written. It is also not unfair to point out that several psychologists have complained that their own book publishers have made exaggerated claims. Do you suppose these untrue advertisements are for benefiting people in crisis or for profits? Did you ever see a publisher recommend that you look up his/her best books at the library?
Publishers seem to believe that people will not try to generally self-improve or prevent problems. We readers are assumed to be so stupid that we will only seek help after we are in trouble. Therefore, the self-help book industry publishes books about specific, serious crises which will drive us (while in distress) to buy their books. Fortunately, many of those books are written by experienced professionals and are quite helpful. However, truly effective self-help education should emphasize early detection of problems and prevention, as well as crisis intervention. Prevention is sorely neglected (discussed later).
What are other consequences of primarily publishing specialized (one topic), crisis-oriented books? For one thing it may discourage the ordinary person from reading self-help books. If self-help books become associated with weird problems and serious crises (such as depression, addictions, abuse, divorce, etc.), it might strengthen our belief, as long as we are coping barely adequately, that "I don't need to know or think more about psychological coping unless I have a real serious problem." That's wrong but it fits with our desire to feel capable. (Note that talk shows have become so associated with rare and bizarre behavior that many people have lost interest and become scornful, feeling the talk show topics are weird and unrelated to them.)
There are other problems related to the emphasis on thousands of books with a very limited scope. Examples: Could such books be used in a group or class where people have many kinds of problems? No. Will reading one specialized self-help book give you general knowledge which you can apply to different kinds of problems? Probably not much. When you are having serious problems, are the difficulties usually limited to just one area? No. Is it common to buy a book for a specific problem and soon discover that you don't really have that problem? Yes (perhaps that is partly why 90% of self-help books never get read beyond the first chapter). Is it reasonable for every specific problem to require its own self-help books? No, although that would sell more books, wouldn't it? Do the thousands of unique problems require thousands of different methods for coping? No. This is an important point, let's look at it more closely.
There are only 15-20 self-help methods for changing our own behavior, no matter what problem or crisis we are having. Likewise, there are only a few basic methods for controlling emotions which are used in all upsetting situations. The same for learning skills, changing our thoughts, uncovering unconscious factors, and so on. In short, it is easier and better to know the general principles of behavior and the basic methods for changing than to study hundreds of seemingly unrelated problems. Therefore, 20,000 self-help books are an overkill. A case in point: this book deals with hundreds of problems (chapters 3 to 10), but the methods for coping with those problems are described in entirely different chapters (11 to 15) because the same method will be useful with many different problems. What we all need is comprehension of the general principles of behavior and changing, as well as carefully designed research (not necessarily by professionals) testing the effectiveness of self-help methods. Our knowledge needs to be integrated and unified, rather than split into little atomistic books. This brings me to the last major point.