1, bitcoin has no value, just a piece of junk number. it has no value like currency or gold, people buy it just for speculation.
2, bitcoin is unsafe and easily be stolen. If someone buy some coins for invest, it may disappear or hacked.
3,Gov will ban it, because it is anonymous and can not be controlled. People can use btc buy illegal goods like drugs and guns, and may not pay tax. Or terrorists will use btc to fund terrorism activities.
4, Btc system is unsafe too, 51% attack will destroy it.
5, people does not need bitcoin, they can use dollars as well.
So I think btc will soon die.
Why Bitcoin will live:
1)Bitcoin has a value as long people buy and sell goods and services with it, companies integrate and adopt it, and exchanges still transact it
2)Bitcoin can be safe, secure, and not easily hacked if you transfer to offline, cold wallets, create backups of your wallet.dat or paper ones, and buy from trusted, secure exchanges like Coinbase.
3)Government has no reason to ban it, in fact, they're in the process of trying to find ways to regulate it. People buy illegal goods and drugs with fiat numbering in the billions every day. Terrorists use any sort of currency they get their hands on to fund terrorism.
4)BTC system can be secured and 51% attack avoided if more nodes are present processing transactions, and the large mines are not pointing to the larger mining pools, but rather p2pools or solo mining.
5)People want options, not everyone has a banking or checking account, or can afford Western Union fees for remittance. People in Greece, Argentina, Asia, Africa could use something better than the currencies that their floundering economies and governments are forcing upon its people.