If we talk about Bitcoin then there is lot of evidence available that success lies in long term trading and there is very little probability of getting success if you are a short term trader. Just see results of DCA or Lump Sum over a period of 5 or more years and one can easily figure out why it's important to invest for long term in Bitcoin. Those who don't have much time to look market on daily basis, it's best for them to invest for long term. In this way they can guarantee themselves good profit and also free themselves from hassle of looking into market on daily basis.
Yes, we have heard of many people becoming rich through bitcoin but most are long term holders, I have not seen or heard any stories about someone becoming rich through trading short term with bitcoin or any altcoins. That shows that long-term investing is always a much better choice than short-term trading.
I am not against someone engaging in short-term trading but it is clearly not a good option if we want to get rich with bitcoin. Short-term trading is only suitable for us to take advantage of to make small profits in a short time, never think that thanks to it we will become rich. That's too risky because we all know that bitcoin is very volatile and unpredictable in the short term.