Do they really? I often encounter this statement. And i have no idea as to why. This past few days, bitcoin is on the rise and most certainly than not altcoin's price surely follows. I am not saying this is bad but altcoins have very little in common with bitcoin. And they are certainly not carbon copies of bitcoin either. Why the heck is their price so closely connected despite being so fundamentally different?
That's because everyone is waiting. When Bitcoin rises, then we will start buying Bitcoin. Some buy with altcoins, and altcoin prices will be cheaper while Bitcoin rises. If this lasts long enough, many investors will begin to be interested in buying altcoins, and a lot of fiat money starts to enter, and in general all prices will increase.