Quote from: hannaaye on February 28, 2018, 10:09:54 AM

(2) Security
Blockchain is also an address, a password, and there is not much difference from an account, if the frauds get the password, they can still embezzle it.

wrong analogy. the only thing stored on the blockchain are transactions which have nothing to do with address, password or anything like that.
the security also has nothing to do with the blockchain. it comes from the cryptography that bitcoin uses.

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(3) Scarcity
One of the reasons we use cryptocurrency is that we can avoid the inflation, but both Bitcoin and Ether have succeeded in making hard forks several times. In addition, coins value is uncertain.

first of all ETH is not scarce. there is 6 times more supply of ETH than there is supply of bitcoin and also ETH has no cap while bitcoin is capped at 21 million and that cap is the scarcity

second, forks does not change anything about scarcity of bitcoin. they are poor copies of something good.

so far none of these 3 had anything to do with your title!

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Besides, most of the cryptocurrency exchanges platform are centralized, they seems work well. Do we really need the decentralization of the blockchain?

again this has nothing to do with decentralization.
exchanges are third parties that are using the technology to offer some services. they don't define the ecosystem.

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BTW, there is an ICO I heard pretty interesting, a hybrid decentralized exchange https://joyso.io/. Is it worth to invest in?

did you create this topic to advertise this ICO?