You can do a simple analysis on your own but they are very unreliable since markets have trends as a whole and as individual components. Meaning in general, something will follow the trend of the market and only have slight variance within itself.
The program doesn't tell us what to buy or sell, but it produces market trends that we can use to help predict that of the other thing...
By the way, little word of advice: your ad hoc argument is the same as telling a construction worker that since a drill screws in his screws, that he doesn't know how to screw in a screw... Sounds stupid doesn't it?