In my eyes volatility is what is preventing crypto currencies from being more used for payments in online commerce.
I believe that crypto currencies are much better adapted than credit cards for online payments (faster, cheaper, non-reversible, simpler, etc). And yet crypto currencies are hardly used at all:

BTC is 300x more volatile than EUR
I strongly believe that lack of adoption is due to the crypto’s volatility. Merchants have costs in fiat currency (USD for example). Having a BTC price for their product that changes by 30% a week is not manageable and provides poor customer experience. Imagine if you wanted to buy a car and the price was today 10 BTC and tomorrow 13 BTC and day after 7 BTC while the normal consumers haggles over $200 for the price of the a $40,000 car and needs hours/days to make the payment. This is not manageable.
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