Trend lines are drawn on charts to help predict the general direction of price.It also help to determine good entry and exit point.they also help to see the reversals.
Sometimes may reverse and take you to the loss land till and we should really create trade by reading a good trend that just take the opportunity when price is reversal then follow back the trend to gain more profit till Trend is very important as a tool in the analysis till Traders use different kinds of indicators to figure out the current trend in fact Use Fibonacci retracement along with bollinger band then It is hard to recognize the trend up or down which we know is the price moves upward and downward price move.... Sir you are right here but following trend line is necessary to understand the next expected market movement, sometimes market moves according to history and sometimes market moves due to excess buying/selling of currencies, and sometimes market moves according to upcoming news, so it is difficult to tell the expected next movement but not impossible so you must be able to earn.