Buy and hold strategies are often recommended for long-term investors who have time to ride out the ups and downs in the markets over a period of years. They are also typically appropriate for novice or uneducated investors who do not understand the markets but still need long-term growth or income.
Market timing strategies may work in any time frame as long as the market is timed correctly. This, of course, does not always happen, and no timing strategy has ever shown itself to be foolproof.
Which investment strategy do you prefer?
As long as you can find the best time to buy and best time to sell, i am sure it is more profitable than just holding.
but it is more safer if you just hold your coin because you can avoid the chance to loss on the market bad timing.