This is because the value of the share is not
set by the company or the stock exchange but by
the buyers and sellers who make up the marketplace.
A share like everything else is worth only whatever
another person is willing to pay for it. This is the
challenge and excitement of the stock market, and all
techniques of investing, whatever CNBC says, ultimately
rest on this fundamental premise:
that when the time comes to sell, the investor will find
someone who, for some reason, is willing to purchase his
shares at a price higher than the investor originally
paid for them.
In other words, when all is said and done, stock market
success is largely a matter of mass-psychology, with the
investor trying to guess just what sort of stocks future
buyers are willing to pay more for.

So in many ways, an investor is trying to predict the
future, which is unknowable and therefore knowledge
of what's currently happening in business, in the economy
and the world is used as a substitute. Thus we are bombarded
with all these statistics in the mass media. The investor
has to be very careful not to drown in these statistics,
because ultimately he has to sell his shares to people
and not to statistics.

Even if you were to read all the books, surf all the message
boards, listen to the self-proclaimed experts in mass-media,
when you buy a stock, you are maing a decision based on
gut feeling. Research only hopes that you be making an
intelligent decision.
Greed and fear are the only two forces that drive people and
in turn the market.

In summary, this message should be very clear:
Never assume that anyone knows more about the stock
market than you do. The stock market, like the future, cannot
be predicted. People who make correct forecasts are not gurus,
they are just lucky. Anbody can say a stock will go up or down.
Nobody can predict the exact movement in dollars.
Your guess has to be as good as the next
person's. For you, it's probably better, because it's personally
suited to your own needs - psychological as well as financial.
This is crucial.