Normally there are people whom we call day traders, this day traders earn is  to trade and make profit daily which required more knowledge to carry out technical and fundamental analysis, this people are the ones that belong to the buy buy buy and sell sell sell category because of price movement.
And there are also another category of people whom we investors their earns is to buy and hold for long term, nothing like buy buy buy or sell sell sell for them, weather the price is going up or down they are still buying continuously, this are people who are committed to there investment vision. You just need to have little knowledge about crypto to belong to this category, no time to stress yourself to carry out technical and fundamental analysis just stay inform that's all you need.