Charts tell you nothing. The value of an investment depends on it future value. It's past value is irrelevant.
Every stock market and exchange in the world use historical charts. They use sophisticated analysis software to predict how the market will behave. Are they all wrong?
In short, yes.
I can tell by the words you use that you are an investing newbie. Here is my advice to you: Investors make money because they learn, they do research, and they uncover opportunities. There is no magic formula. There is no secret system.
People that believe that they can predict the future by looking at charts are nothing more than financial astrologers. Technical Analysis pretends to be a science, but the truth is that it is based on fantasy and superstition, and it is supported only by confirmation bias.
That is true. However, there is some kind of self-fulfilling prophecy aspect to that. If sufficient traders use the same intrinsically worthless techniques, and hence come to the same silly conclusions about buying or selling, then those initially worthless techniques DO become true predictions of the future (at least as long as there are no other demands and offers than those from traders).
It is funny, because "technical analysis" has the same "next fool" property as money in itself: technical analysis is only worth something if others think it is worth something concerning the prediction of prices. The specific algorithms used in technical analysis can be totally arbitrary, as long as sufficient people use the *same* algorithms. If there is a prediction algorithm which is as silly as "at full moon prices go up by 10%", and if sufficient people BELIEVE that, they will buy just before full moon, and have the prices rise up to 10%. Not more, because then their algorithm tells them that the asset is somewhat overpriced as compared to their "prediction".
So, technical analysis algorithms behave as money: if sufficient people think it is worth something, then it IS worth something.