For me both doings is good, it depends on how you use your bitcoin both choices is profitable because as you hold it tgere is possibilty that it will double your investment while buying it during low price and sell it higher can gain you also profit. So it is a matter of each of us decision.
Yes of course. Both are more profitable, when you buy at low price, it is a good choice to HODL it first and wait until the price reach its peak. That's the basic strategy which effectively applicable in having investments on bitcoin to get huge profits in the future.