Selling your bitcoins is a matter of choice you can decide to sell it when and how ever you want,it's your choice,so what ever decision one makes concerning buying or selling of bitcoin is up to them.
But if they are here for getting the profit then we have to guide them if they do not know that what is the time to buy and what is the time to sell as if they will not follow the rules and they will not know then they will spread negative news that there is lose in bitcoin. If we will guide them then they will be fan of bitcoin and will promote it more and the price will increase.