Investing in "value coins", a classic case of 10 million turning into 10,000
ICP: up to $2,800, now only $6.9
FIL: up to $430, now down to $3.6
ZEC: up to $2,000, now down to $18
EOS: up to $23, now only $0.49
AE: up to $2.3, now only $0.023
In addition, there are many countless altcoins that have been delisted and returned to zero.
Therefore, it is best not to hold any non-mainstream altcoin for a long time.