"Chart history and fundamentals confirm their decision."
With all due respect Junglewoman, I think you have the cart before the horse.
If you don't examine the "fundamentals" or "chart history" prior to purchasing, how do you identify the company in the first place? By the aforementioned d/A?
"Basically people sell if they think the stock is out of favour" ... how do people come to the conclusion that the stock is out of favour if not via technical analysis (even if it is the most rudimentary, like, the price is falling?
"And people buy because they think it's a bargain." .... how do you decide what fair value is without F/A.
No, I'm sure that most people do at least some F/A &/or T/A before they make a buy decision & more often than not before a sell decision ..... but then again !!
