I've seen things you people wouldn't believe. Attack ships on fire off the shoulder of Orion. I watched C-beams glitter in the dark near the Tannhäuser Gate. All those moments will be lost in time, like tears in rain. Time to die.
Roy Batty (portrayed by Rutger Hauer) in Blade Runner
We are our experiences; when we're gone, they're gone. And so, we try to pass them on, but this is always inadequate.
Language only works if the people using it have enough shared experience for the words to effectively communicate the thought. If you try to explain an experience to another person, they have to have had the same or at least a similar experience in order to understand what you're talking about. As Wittgenstein points out, “if a lion could talk, we couldn't understand him” – this is because we don't have enough shared experiences with the lion to understand what a lion might be trying to communicate.
Imagine that you've seen God – how would you explain the experience to someone who hadn't? We can't even adequately explain the taste of ice cream, how can we explain seeing God? This is the primary problem for the mystic who tries to communicate the experience.
The handiest of the marks by which I classify a state of mind as mystical is negative. The subject of it immediately says that it defies expression, that no adequate report of its contents can be given in words. It follows from this that its quality must be directly experienced; it cannot be imparted or transferred to others. In this peculiarity mystical states are more like states of feeling than like states of intellect. No one can make clear to another who has never had a certain feeling, in what the quality or worth of it consists. One must have musical ears to know the value of a symphony; one must have been in love one's self to understand a lover's state of mind. Lacking the heart or ear, we cannot interpret the musician or the lover justly, and are even likely to consider him weak-minded or absurd. The mystic finds that most of us accord to his experiences an equally incompetent treatment.
William James, The Varieties of Religious Experience
I contend that most mystics never attempt to explain their experience or quickly give up trying. Thus, it seems to the general public that there aren't that many. Maybe you know one; maybe you are one.