There are a few myths and misconceptions about therapy.
One common one is that "happily ever after" myth. We often believe that therapy works much like dental care, for example, where you go to the dentist when you have a problem to get it fixed and you can then return to the way you were living before. However, toothaches have no bearing on your past or your future, and have nothing to do with who you are or the way you see life, while this is not the case with therapy. A therapist can't change your childhood, or your relationship with your parents, or other experiences you may have had that have led you to the point where you are today. Therapy allows you to talk about these matters so that you can have a better relationship with them and reframe other thoughts that may go through your mind on a regular basis. Even though therapy may not be the immediate "cure" that you seek, it allows you to manage your thoughts and relate to them more meaningfully so that you can move forward differently.
Another myth is that therapy is endless, or that going means committing for the long term. Therapy can last for any length of time, and it varies for each person. Some people may find that they still like having a third-person expert to talk to even after their initial problem has been resolved, and keep seeing their therapist for this reason.
One other common myth is that therapy just involves lying on a couch and talking about your problems. While this method is true for a method of treatment called psychoanalysis (as discussed earlier), for the most part seeing a therapist will not involve any lying down - often, you will be sitting face-to-face with your therapist having a genuine conversation with an independent expert who is trained to help you.