I think hgibbs is confused between puts (a contract for the ability to sell at a price) and shorting (borrowing to sell immediately and buy back later), but your comment isn't quite right either.
Shorting has unlimited downside, since it may be arbitrarily expensive to buy back the shares/coins that you borrow.
Puts, on the other hand, have a strike price. A contact to be able to sell Bitcoin for $30K is worthless on the expiration date if the market price is $40K. Anybody can sell at a better price than your contract on the open market. The market price going to 0 is the best thing for the owner of a put option. "Stocks can’t drop below 0." is actually a bummer for the put owner. If a stock could go lower, the put owner could sell the asset for even MORE than the market price of the asset.
What hgibbs probably wants to hear is this: The worst case for a put owner is for the put option to expire worthless since the market value of the asset is greater than the strike price when the option expires. The maximum downside is a contract worth $0.
If you want to pay a premium to be able to sell bitcoin at the end of the year for $20K, but the value is still $30K on December 31, your put option is worthless, and that's as bad as it gets.
...UNLESS you're buying puts on margin without a stop-limit.
My question was in relation to the parent comments claim that buying puts can cause unlimited losses - I was pointing out that this was wrong. The original comment seems to be edited now
Shorting has unlimited downside, since it may be arbitrarily expensive to buy back the shares/coins that you borrow.
Puts, on the other hand, have a strike price. A contact to be able to sell Bitcoin for $30K is worthless on the expiration date if the market price is $40K. Anybody can sell at a better price than your contract on the open market. The market price going to 0 is the best thing for the owner of a put option. "Stocks can’t drop below 0." is actually a bummer for the put owner. If a stock could go lower, the put owner could sell the asset for even MORE than the market price of the asset.
What hgibbs probably wants to hear is this: The worst case for a put owner is for the put option to expire worthless since the market value of the asset is greater than the strike price when the option expires. The maximum downside is a contract worth $0.
If you want to pay a premium to be able to sell bitcoin at the end of the year for $20K, but the value is still $30K on December 31, your put option is worthless, and that's as bad as it gets.
...UNLESS you're buying puts on margin without a stop-limit.