That's right, money goes and will come again. If we still have the opportunity to make money, we should not regret the past. The ultimate goal when we invest is to be able to make a profit and we should be satisfied with that.
So far, we can almost say that the growth of bitcoin is certain but with bitcoin's past still ambiguous holding it would be risky and we regret assuming bitcoin will not increase. Always set a price target for yourself, don't be too greedy greed will sometimes kill our future.
That's the point why we are investing and trading right and that is to earn profit. For me, it is depend on a person on when he is going to plan to cash out his long term holding assets but in my case as long as the current market price of a crypto that I am holding is enough already to say that I've earned a profit from it then I am not hesitated to sell it. There are times that we may encounter unexpected instances that sometimes our savings or our long term assets in hold may need to sell for emergency then it's a win-win already.