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.... In order to lose, bitcoin would literally have to crash nonstop from the day on where someone decided to get in. How likely is that...?
We could have several years of portfolios ending up in the negative, so bitcoin is not guaranteed to go up, even though right now it seems that there is quite a bit of upwards momentum... yet personally, I doubt that the strategy for any bitcoin newbie should change, and it seem to me that any newbie should be considering to put plans in place to buy as much bitcoin that he can for at least a whole cycle, and then perhaps reassess after that... and surely some folks will get distracted by price, and it can be quite difficult to figure out price, and from my own perspective price may not matter that much to a newbie, especially if he is largely just drawing a certain percent of his regular income.
Surely if a newbie has large opportunities to front load bitcoin by lump sum investing or other ways of front loading, then he might get himself in a position to adjust his strategy sooner than 4 years, otherwise, it seems that newbies should largely just be attempting to accumulate BTC through ongoing, persistent, consistent and perhaps aggressive buying for a whole cycle.. and then reassess thereafter. Everyone is responsible for his own decisions and actions, and even failing/refusing to invest is a decision/action.
It is never guaranteed to go up of course, but I am not talking about the momentum that is currently there. I am more talking about all the things that happen around bitcoin apart from the fact that it had or is having a bull run. If we take 4 years as an example and someone does decide to do DCA as of today, the person would have to have very bad luck to lose a significant amount of money over the course of those 4 years consisting of frequent purchases, like monthly. No doubt it could happen, but it is unlikely as governments and institutions and corporations are discussing bitcoin more than ever. Since it is hard coded scarce and there are not that many bitcoin, if someone now buys on a monthly basis, the timing would have to be incredibly bad and the performance would have to take a U-turn or go down consistently for months and months and not go up again, such that upward movements would not be sufficient to former DCA purchases that went negative and cannot make up for gains made on the latter purchases at lower prices.
There is no need to explain it to you, but a longer time horizon with regular purchases ending up in losses would be quite surprising in my opinion because no matter where the price goes within half a year or a year, actually going down over the course of four years consistently is something I don't see coming. I am not ruling out the risk entirely, but if I was highly skeptical and thought this is a serious risk, I would probably be more conservative about bitcoin's future.