There's an old saying "Buy when the market is green and sell when the market is red".
It's arguably one of the better strategy as your money won't remain stale. When you see a bullish trend, you buy the first moment you can and when you thin it's turning into a bear, you sell. Short term investors earned a good profit in last 1 month as compared to holders that are holding for last 2 years. Different people have different strategy when it comes into trading but the essence is to increase your profit while limiting your loss.
profits be main goal for each traders, no matter strategy they used to realized it. some expert said like you and other people have different opinion. all of that was true, the wrong thing was when we as traders could not do this proverb and always do wrong strategy and not learnt from experience.