In as much as Bitcoin investment is concerned,it takes the strong hearted to invest in it,even when using the DCA method or otherwise because of the fear of the unknown about the market price and alot of risk involved in it ,when using DCA method, it helps you accumulate and manage your resources to constantly be in the market,since it does not have a fixed amount to buy, instead you buy what you can afford,DCA method remains the best method of accumulating if you choose to buy bit by bit no matter how little it might be,you keep growing.
This statement you made here makes things look as if bitcoin investment is some kind of Ponzi scheme in which the money you invest in it is under 90/10 chances of getting it back.
To invest in bitcoin does not take the strong-hearted; rather, it takes those who understand what they are investing in to invest in it. If you know what you are investing in, you don't need your heart to be as strong as a rock before you make your investment decision. Those who don't invest do so not because they have a strong heart or a soft one but because they know what they want and are willing to sacrifice a little of their earnings in an asset that's worth it.