Hypnotherapy is a strange and mysterious thing to most people. Clients who come to be hypnotized are often uncertain of what to expect. Many are secretly convinced that they can not be hypnotized, are seeking the session out of desperation. They really don't expect it to work. Many of them are therefore ready for it not to work, and will use anything as evidence that they are right.
There is one simple thing that every hypnotherapist can do to increase their success - convince the client that they were hypnotized. Success is a matter of meeting the client's expectations. If the client believes that they were not hypnotized then the hypnotherapy is unlikely to work as well as if they believe that they were. So it is good practice to always find a way to convince the client they were hypnotized.
One simple way to increase hypnosis success
Some people assume that because they can remember everything, they must not have been hypnotized. Others expect to feel somehow strange or bewitched in some way and are disappointed when they don't feel that way. Others expect to wake up feeling totally different and that their life will instantly be transformed when they open their eyes. This naive set of beliefs works to prevent a successful outcome.
Therefore the therapist has to demonstrate to the client, clearly and unambiguously that they were in trance. It has to be proved to every client, every time.
Use eye catalepsy to increase hypnosis success
The easiest way to do this is to test for eye catalepsy after the induction. This lets both you and the client know that the client really is in trance. I have trained myself to always do this. When I started out as a hypnotist I was often afraid to do this test, just in case the client wasn't in trance. I have since learned that if the client opens their eyes then you both have learned something valuable. The other simple convincer is to do a finger lift at some point in the session.
A method that is used less often, but is probably better, is to talk to the client in trance. Ask them what they are experiencing. Again this is very illuminating for both parties and rapidly builds the confidence to use regression and metaphor therapies.
Building in a convincer takes only a minute or two, and is well worth the extra effort.