The Fear of missing out (FOMO) has made many people to go into debts and ultimately forced to exit the market when it is not yet time to reap the profit of their investment.
Fear of missing out is one of the factors that brings failure to investment however most people has actually fall a victim of Bitcoin market structure, were as they believe that since the Bitcoin price is a bit lower, they try every means possible even to the extend of getting a loan in other to accumulate a huge number of bitcoin because of the fear that they may not get the right chance again to see Bitcoin on that particular price and that perhaps the bitcoin price could moves very higher than there expected entry points.
So actually you are very correct this was a similar issue my colleague had, he saw Bitcoin when the price was still at $25k so considering how far the price had gone before when it made the all Time high so he sees it an advantage to accumulate good number of Bitcoin while he can now so he tried every means possible by using all his savings to acquire the Bitcoin in other not to miss out this opportunity, so it was a good move but the strategy was very aggressive because he had use all his savings in accumulating the Bitcoin and was not upto a month he started feeling the heat due to some pressing needs so he start panicking and the investment became affected and was left with no uption but to sell it off.
Although he was very lucky that before those pressing needs came out, the Bitcoin price had already gone beyond his buying point so instead of losing he made a bit profits, so with that experience he had, he was able to encourage people of the consequences involves on making a rash decision due to the fear of being left out from investment, so no matter how Bitcoin price may drop down is very unwise using all you have to accumulate Bitcoin because later on it may seriously affect your investment, and perhaps in times of Bitcoin no time is late, we can always invest whenever we feel we are ready, but the only different is that it will take a longer time to gather or accumulate your expected amount due to the price increment.
Your friend didn't plan on how to accumulate Bitcoin, but rather he entered into the market blindly, and you couldn't put him through that the way he is rushing his bitcoin investment purchase with all his savings, is the same way he will rush out of his investment. Bitcoin is not something that you use all the funds on you to buy without reservation of fiat currency for his emergency funds or his basic needs.
There are sometimes that even the funds that we reserve might not be enough to sustain whatever emergency that occurs and if such happens that investor will have no option than to sell his investment and that was not his plan to sell quick. This is why one must prepare very well to make sure that whatever unforeseen challenges that comes your way,you will be able to settle it without touching your bitcoin investment, to enable you keep on accumulating on your journey to your bitcoin target that might take maybe 10yrs and above, depending on how much that your income is and how much you funds that you have assigned for your weekly or monthly DCA.
What happened to your friend was that his aggressive buying made him to lose focus on hodling his bitcoin for long which was the plan because he used all his savings to buy Bitcoin, and at the end he sold all he has bought. I wouldn't say he gained any profit because assuming he bought with the little money that he can afford to lose and continues to DCA with 10% of his savings, he will be increasing his bitcoin investment portfolio gradually and he will be able to do this for a very long time, where he will make a good profit compare to the peanut that he made. They worst of all is that he didn't have any bitcoin investment anymore, based on lack of plans and he bought aggressively. Same thing is what will happen to people who fill that they are starting their bitcoin journey late and invest aggressively, they will end up losing all their investment early and shatter they dreams of having bitcoin as their future investment.