when you do trading, do you always think about this, "buy some, sell some, hold some."
I believe that every successful employee of cryptocurrencies should do 3 of those in the same time, buy some coins hold some coins and trade some coins, three points of success.
sometimes buying is not applicable since you can still earn by offering your skills and be hired and got a job then your salary will be put for holding and selling you coins and sometimes it can be used for trading to earn more coins.