"Stealing opportunities" - disagree to this. These markets are based on speculation and there are several opportunities. We must admit that we often fail to recognize them.
It is based on speculation, you are right with that, however, if you are discipline enough to hold, you should not fail because the market can be bullish as well. Just make it simple, if you hold for long term, you need to ensure a target is already in place, for example, you buy bitcoin at $19k and you plan to sell it when bitcoin rises to $100,000, then you have to hold until that time will come, otherwise, that's the real meaning of missing the opportunity.
but, first, you need to believe that bitcoin could reach $100,000, when you are convince, holding until that time will come should give you an ease.