Basically it all depends on yourself in selling bitcoin because everyone has their own investment goals, each investor's target must also be different. So stupid ideas or smart ideas all depend on your choice, because in my opinion the goal of bitcoin investment for everyone is to seek profit not to hold bitcoin for life.

Moreover, bitcoin has a cycle that we can use as a reference to make decisions when to buy and sell. If you sell before ATH it might be a stupid act, but if you sell it when bitcoin ATH is reached it is a smart choice. This is the importance of every investor to be able to manage this risk management so as not to make the wrong decision. The point is when can you sell bitcoin intelligently? when you feel that the profit you get has exceeded expectations then selling is a wise choice, then you can buy it back when the price is down.