it's very difficult to buy low. you may you think buy low, but the price is goning to down, then you can't sell high, only to hold and wait.
so, hold your bitcoin is the best investment./
Yes sometimes it happens. Because the strength or low price of each person is different the research is different and I've experienced it myself I went to buy altcoin which I think was at the low point but he came down after I bought it and I tried to buy back at different prices but he did not want to stop and finally I survived and waited for him back at the pump