This expression really irritates me when it is applied to bitcoin.

It is a seemingly intentional (or even ignorant) perception of the risk of bitcoin, and tries to suggest that bitcoin is more risky than it is or that we are gambling when it comes to bitcoin.

Any of us can look at bitcoin's volatility history and choose the amount that we would like to invest into bitcoin base on viewing such history and anticipating that the volatility is likely to continue... so then we can also choose our position size accounting for the volatility.

If we are overly concerned about downward volatility or losing money, then we can choose a smaller position size in order to attempt to account for our concerns.

Another thing is that if we have a 4-10 year or longer investment timeline then we should anticipate that there may well be ups and downs along the way, and sure, buying and holding and continuing to buy through the period until we have enough should be the better approach and perspective rather than anticipating that we are going to be trying to trade or predict the directions of waves, which may well not end up playing out too well for us, especially if our goals might include the ongoing building of the size of our bitcoin holdings and hoping that the value of our BTC holdings will ultimately end up going up during the time that we are building it... even though in the shorter timelines the value may well go up, down and sideways.

And, so yeah, if there is no guarantee that the bitcoin investment will ultimately be up, then we can figure out what we want to do or need to do along the way, if we are going to continue to build our bitcoin investment for the 4-10 years or longer that we might know is a better timeline, or if there might be times along the way that we feel that we have to, need to, or want to take some value off of the table. Those are our perception and action choices... and surely, there are quite a few folks who end up selling too much too soon, but we still have choices in regards to if we might end up going down that path, and sure maybe some day, those guys who sell a bunch of their bitcoin, they might end up being correct in their choice to sell.  There are no guarantees, either way.