Are really serious about this factor that bitcoin's price are fluctuating and not a better thing for us .
Here you are true that the price of the USD changes from 2-3%+- which is making us sure that we have money that is have the same value during the time when we got , But here is another factor is that why not we should think that the money we got should increase daily .
That is only possible with the bitcoin or another cryptocurrency payment .
Here we should see the fluctuations in the price of the bitcoin in positive ways , because this is the unique quality of the bitcoin that why the people like it much than what to another currency .
So here i don't think we should say that bitcoin can't be worldwide international currency because people are using already bitcoin for the payment purpose and at all possible places , so you can expect what will happen after 2-3 years with the virtual currency world .

it is true, bitcoin can not remake world currency ,  because base bitcoin is cryptocurrency, and bitcoin prices are unstable. bitcoin and altcoin are the means of choice or sub currency as a means of payment.

Why is BTC volatility so high? The reason being BTC is far from perfect. Any FUD even from cats and dogs are enough to shake up the market movement. Crypto as a whole is also not as understandable as much yet so that could also cause a lot of misunderstanding!

bitcoin does not need to replace currency at all. As you can see, without the mass adoption come from the government, people still use bitcoin as an investment and currency. And the only thing that stop bitcoin from being a world currency is not the stability, it is the price of bitcoin. The price of bitcoin is very high right now which make it the same as gold. And people only hold gold, they not use gold as a currency

Yes, I agree that Bitcoin can not replace any fiat currency but I don't think the volatility in the price is the main reason behind it. First of all, it should be legal through the eyes of law so that everyone would be able to use it legally. Then, since it is based on digital infrastructure, we don't have that level of environment in every part of any country and it is risky to rely on the web currency, because of such reason

* Somalia's internet outage costing country $10 million a day.

Thus as of now, it is almost impossible for any digital currency to replace any fiat currency unless the country is Sealand.

LOL. I don't think so dude, if you think real cash is stable I think you're wrong cause it's not stable as you think ) If you don't believe me you can take your money to buy fuel or gold today and the next day ) I ensure that the rate will be different because real cash also do not stable dude, its value is changing everday

It is not necessary that we should keep it restricted to the internet currency. We should take efforts to bring it to offline market too but I think we should not rely on it in that sense. One would definitely use Bitcoin for his offline market transaction but only when there is an advantage for him to use Bitcoin. It practically doesn't make any sense if I am asked to pay Bitcoin transaction fee which is equal to the cost of bread if I am buying that bread.

for me i see Bitcoin is the fusion from forex and stock, because bitcoin have volatile price as you said and more people using bitcoin just for investmen and don't wanna use as payment because the price. so people that have much money save it as invesment, and other people use as trading.

Bitcoin can not replace currency in the world, because Bitcoin can not be used in shops. Shop cashier will not wait for Bitcoin confirmation, which can be up to 20 - 30 minutes and more. Bitcoin can not be used in shops, so Bitcoin is not usable for wide public use.     

It will come to stable soon as more people are using day by day, so far I seen it really fluctuates and the drop is like reaching to the earth on once.
Still it shows the rise in USD per Bitcoin and may increase from my side in future.

Investors always get trouble investing in any things, if their is 99% profit then all would turn into bitcoin investors.