Selling Bitcoin could be beneficial especially when the rate is high. However the timing here is very crucial and you need to also trade in a hefty amount to earn a decent profit.
Selling high and buying low is good but in situation if you have no money to invest you can earn money then buy bitcoin and hold,. at very first try not to sell your bitcoin till it has potential to increase when you will see that there is no more space for price to rise this season, only then think about selling your bitcoin but if not then no need to sell it, market fall and rise all the time so buy when you see market is down and sell when bitcoin reaches at peak, well I am planning to hold my bitcoin till it become 100k, this year.