The mistakes of some bitcoin investor and traders is they think that there is just one strategy in order to make profit in buying and selling bitcoin without knowing that there is unlimited pattern and combination that they can do to make money. One of it is what I do is I'll just ride the trend, if the market is bearish then it is better if you will short and sell it once the chart shows signs of streght creating highers and higher lows but if the price is bullish do not ever fight the trend and you must ride it by doing long because the price will keep appreciating if you do that and your btc value will also increase.
You are now talking about trading, but this is not interesting for investors, or rather, they simply do not want to spend their time on it, they gain a position at some point and then simply wait for their goal, wait for the exit point to take profits.
Following the trend is a good strategy and you can make good profits if you spot a trend change correctly, but it is just one of many ingredients for successful trading.