Very much ,ever since you were brought into this world. when you coulden't open your mouth till the first two years on planet earth, inner voice is the one through which you interpreted and understood things.
Inner voice is the voice mouth of the subconscious mind .the subconscious mind is always acting as a secondary reflector of thoughts and ideas in the body. It justifies and rationalizes what is right and what is wrong. When we go aganist what the inner voice say we get a guilty conscious and are bothered by it throughout our lives.
At times when we are feeling low or those unforgettable moments when we are let down, we seem to need some kind of emotional or mental support. We usually speak to our closest pal or our dearest family member during times of distress to ease the burden .At such times we get over the initial drizzle of emotional anxiety and mental restlessness,because of the pepping up by our empathic listener. we suddenly feel rejuvenated because our inner voice alerts us to get on with things and leave the things of past on the memory books of our brain.
The inner voice is always right most of the times because it knows us better than others and probably even ourselves. It is the dare devil child of the intuitions which we have been having since childhood. It's good to go by intuitions most of the tims because its the response provided due to the synchronism between our mental and physical being.
Whenever you are trying your first cigarette, or whenever you are asked to take sides in an argument, you are always in a sense of dilemma. During these times your inner voice automatically gives its verdict, which when over written, might leave us unhappy in the future. It's up to us to either ignore the morale booster inside us or go out to the world and search for spiritual guru's and happiness, when all these things are very much present within us.