Sometimes people do become their own worst enemy since there can end up being pretty severe consequences if they have not sufficiently and/or adequately prepared themselves for a variety of scenarios, including extreme scenarios and even including the price going against them in extreme scenario kinds of ways.
Bitcoin remains amongst the best, if not the best, of investments widely available to people around the world, yet there are people who have lost money in bitcoin, especially if they failed/refused to error on the side of accumulating bitcoin and holding and not going overboard in their various methods (including getting too greedy).
That's one thing some people who criticise Bitcoin don't understand, they'll make errors that would make them lose their coins and then call it a scam, instead of admitting their mistakes and take corrections, in Cryptocurrency space, especially Bitcoin investment, if you do things the right way you'll thrive but if you do others you lose and that's just it, asides Cryptocurrency, greed has been the downfall of many and they don't learn, you don't have to be too greedy to achieve success and it applies to Bitcoin investment too, cause greed can make one vulnerable to scammers that would easily mislead one into the wrong investment and before you know it their coins would be gone then they start blaming it on Bitcoin forgetting it's their actions that caused it. Doing the right thing pays, and when one picks the right choice of investing in digital currency (Bitcoin) you don't ruin it by being too greedy.