I have heard many people say that never sell for a loss but what does it actually mean ?
Assuming you have bought a coin at $10 and the price goes down to $9 but you don't sell.
You could have placed a stop loss at $9 but you take "Never sell at a loss" so seriously that you decide to not put a stop loss.
The price goes down to $8 but you are too good at HODL. Suddenly the market crashes and the price goes down to $5.
You could have limited your losses at $9 but now your portfolio is down by 50%.
Now the price has to go 100% so that you breakeven with no loss no profit whereas you could have bought back at $5 and gained potential profits using a stop loss.
This is why I think "Never sell for a loss" is a myth and we should always use a stop loss and play safe with a good risk to reward strategy.
I don't think this phrase is a myth. On the contrary, there are people who just bought a crypto asset and are waiting for its price to double or more, for example. I think they do not need to worry about what is happening on the market, they have a goal and they are waiting for its implementation. But your words also make sense, because I use the stop-loss function, there is probably an opportunity to earn faster, but this category of people includes traders, and those who are just waiting are investors or hodlers. So there are simply several options for achieving this goal, that is, making a profit, only different groups of people go to this goal in different ways.