Great point Lumaza.
I also call it a form of mental conditioning or asking/giving permission from your higher self.
It is like there is a kind of 'organic' process that needs to take place where the long-conditioned resistance to having an OBE has to be progressively overcome. The resistance takes many forms: from simple annoyances like itches, twitches, tickles, monkey-mind chatter to more energetic exit symptoms that surprise us initially: energy body swaying, spinning, body parts slipping out,..finally to the incredible SP and fear-test hallucinations like all sorts of audio disturbances and full-blown, in-your-face hallucinations.
What helped me and I think can help others is the use of affirmations to communicate with the inner self/higher self/subconscious (however you wish to define it).
"I ask permission of my higher self to have an out of body experience. I want to do this. I am ready to do this and ask for help from my higher self."
Come up with your own wording but make it short, simple and sincere. Write it down once a day. Recite it verbally or in your mind when you prepare for an attempt or go to bed. Say it 3 times. This is a highly-effective form of mental programming.
As new and aspiring projectors, we all initially want and expect to have an OBE in a relatively few number of attempts, but for most of us, it takes more than a few tries...maybe a better target is ten or twenty attempts. That is not meant to discourage anyone, it's just the reality for most, me included. And part of this may be a combination of the actual attempts along with the resulting internal messages being communicated and an internal process (the mental conditioning) taking place.
The evidence that this process is taking place in a steady, progressive manner is to observe the variety of energetic sensations as previously described and littered throughout the OBE literature. The more notable symptoms are the SP, the vibrations, the etheric/energy body sensations, the hypnogogia in all it's forms. All of these are good evidence that progress is being made, your Non Physical awareness is waking-up, coming on-line. I have experienced and read of others having dreams about having an OBE. That is an excellent sign that your inner self is experimenting with the idea, 'trying it out for awhile' per se, from the relative safety of a dream environment.
It can take these seemingly small, baby-steps for awhile, but it is definite progress. Each time, you are getting a little closer to your goal, your Non Physical awareness is developing. Don't dismiss these experiences; write them in a journal and you will further reinforce the process.
Experiencers like Lumaza have also taken the time to give us a great variety of useful energetic visualizations to help 'awaken' our energetic essence, our 'true selves'. If you put in the effort, you will see results.
Another aspect to this is: It really can be as simple and straight-forward as to just request what you want.
Ask and you shall receive