If a new technology appears and that is significantly better than the currently one Bitcoin can lose price.
"Significant" is a subjective word plus this would totally depend on what you're trying to look for. For example, there's a coin that's dedicated for the casino that has zero house edge and it's called Edgeless (EDG) coin. If you're all about gambling and you're looking for that zero house edge casino, then this coin is significantly better than bitcoin FOR YOU. But it might not be the case for most people.
I think the "significantly" better is something that is out of the comprehension of most of us on the present, like Bitcoin concept was out of comprehension of many of us some years ago. Personally, I didn't imagine a currency like Bitcoin working fine without centralized power behind it.
These dedicated currencies are interesting for some activities inside the Crypto-Currency virtual universe, but not enough to rouse a movement around them, not enough to make the community engage to bump them and support them, even because they don't offer any special feature that Bitcoin can't do.
If Bitcoin is dumped to a really low value it can lose reputation and potential investors can withdraw their money.
I honestly doubt that this will happen unless something else have already happened to bitcoin and it already lose reputation and investors. Just recently we had a loss of 6K$ in the price of bitcoin. Normally people would panic sell and "jump out of the sinking ship" but that's not what happened. What happened was more people actually joined in and that's proven by the chart that the price picked up right away after the major dump. It's a good day for buyers.
I doubt about it too, but possible anyway...
If governments ban it or put strict regulations many people will stop investing, decreasing demand, decreasing Bitcoin price.
The only thing that I can think of that the government can do that can actually affect bitcoin is to have some new taxation scheme that's targeted to take down bitcoins and make it really expensive to convert your bitcoins into cash. Banning it will just make people find out about bitcoin. It's totally pointless since it's on the Internet and people have freedom here. (I don't know what would be the case once Net Neutrality is gone.)
Most people are just sheeps, if a government put some fear on them they will retreat and continue their poor lifes dealing with fiat and supporting the chaos their countries are. Few would try to continue using Bitcoins and they would suffer the consequences without solidarity from their countrymen.
If a bug is found, making possible for hackers to steal money easily from holders.
If (bug == exist) then
hackers_balance += everyone_else's_balance
End if
If there was a a bug, the hackers should have taken advantage of it already. There's no bug, hon.
I'm a layman to talk about bugs and hackers skills, but I keep my mind open about it. Technology never stops evolving, maybe a bug can be created.
Like an Antivirus, today you can have the most efficient one, no virus can breach it, but if you don't keep updating your Antivirus in some months or years a virus will breach it, because it was evolved and your defense not.
