It really depends on your criteria for buying assets or cryptos, and a little bit of luck. If you're looking to make a quick buck, then short-term trading will best your best bet. If you're looking to have enough when you retire, long-term trading is your best friend. Long-term trading is so successful because it lies in the fundamentals that our inflationary economy/fiat money will ensure that the assets market will always rebound even if it takes years to get through a recovery.
I prefer to invest in short term because this is the way that usually helps me to make profit in a short time and does not need to spend too much time waiting. Each person will have different ways of making money but short term investment should be encouraged during this time to ensure your safety. I think long-term investment will be more risky and market volatility will often make you lose a lot if not careful.