Because when new bull run will arrive there will be new shitcoins and your shitcoins will end dead or delisted from exchanges which can lead to 100% loss.History is always repeating.
5,5 years old chart:
Surprisingly some coins from this chart are up from then but volume on exchanges is low,so holders of these coins are truly bagholders.
The subtle difference is that 2019-2016 all the altcoins were dumb copy+paste shitcoins and Bitcoin was king.5,5 years old chart:
Surprisingly some coins from this chart are up from then but volume on exchanges is low,so holders of these coins are truly bagholders.
Since 2017 bitcoin is the shitcoin and the rest of the top 20 are objectively better. Some coins like Waves and Steem outside of top 20 are also better.
This time some alts are here to stay.