selling bitcoin at $108k in other to buy back cheap when it dip depends on how long you have hold unto your bitcoin investment if you have hold your bitcoin investment from 4 years and above and you sell in other to buy back it's good less take for example now, less say you bought bitcoin around 2015 when bitcoin was between $150k and $500k if am not mistaken and you sell when bitcoin was $108k it is good investment.
As long as you didn’t sell at loss, then it’s a good investment, when you invest in bitcoin, even if you don’t make so much profits then it’s fine, what am always after is that we shouldn’t sell at loss. Mostly people that do make huge profits from bitcoin investment are people holding for long term, people holding for short period of time do make just little amount of money, that’s why when we are planning to invest in bitcoin for maximum profit, then our target should be for long term.