"Only invest an amount you can afford to lose."
Probably one of the most common advice I've heard when it comes to investing in bitcoin; and I've used it a lot of times too. But honestly, in our current situation where fiat is getting printed like hell, I started to use that statement less and less. It just seems that holding bitcoin is now totally necessary.
Holding is for patient investors. Bitcoin keeps playing with investors emotions regularly and each time it tries to making a move up it keeps going dip. But has fiat gets printed more often it's best to hold and holding implies a money you might not necessary have a need for as the market would definitely keep playing with emotions until it makes it new ATH