Does technical analysis work or not?
From the point of view of conventional statistics, technical analysis should work poorly, if at all, because financial series are pretty close to being "random walks." However, this does not reflect the possibility that astute traders might be able to glean indications of price direction from patterns that are not reflected in purely statistical considerations. In other words, it might be possible to profit from technical analysis, but it's not easy.
Alternatively, quantitative analysis uses advanced models or algorithms to search databases for patterns, and implement automated trades. Such algorithms have the potential to greatly outperform standard technical analysis. This explains the superior performance of the better quantitative hedge funds, such as Renaissance Technologies, whose worst year from 2001 through 2013, saw a 21 percent gain, after subtracting fees. (In 2008, they gained 98.2%).
Therefore, for those traders who have the resources, and sufficient mathematical knowledge, quantitative analysis is an attractive alternative. Approaches based on trend following or mean reversion are possible for individual traders. I'm currently implementing a sophisticated mean reversion algorithm using statistical arbitrage, and after 8 months of live trading, I'm on track for a 50% yearly return.