Quote from: fargoway on August 23, 2018, 08:42:48 AM

Because Bitcoin cannot complete some essential challenges in order to replace the fiat money. For example:

1) transactions last long (in comparison to Visa/Mastercard transactions)

Bitcoin transactions are final. Visa's are not.
If used in daily purchases (and proper implemented), accepting 0-conf payments is absolutely fine.
They are marginal slower than visa payments.

Quote from: fargoway on August 23, 2018, 08:42:48 AM

2) high volatility

Volatility will decrease with adoption.
The more people adopt bitcoin as a payment system, the lower the volatility will be which then again attract new user.

Quote from: fargoway on August 23, 2018, 08:42:48 AM

3) scaling

Scaling is taken off-chain.
With the LN all of these scaling-debates finally should have an end.

When LN is ready to be released and people are starting to use it, the average fee for your transactions will decrease.
And so will the confirmation time. You'll have instantly confirmed (not yet settled on the blockchain) transactions happening.