"It's not functional as a currency. The peaks and troughs are like an investment asset and are equivalent to gold," Dorsey told the Australian Financial Review in a story published Thursday.
"What we need to do is make it more usable and accessible as a currency, but it's not there yet," Dorsey said.
Bitcoin is volatile: It is currently trading at around $10,250, according to digital currency exchange Coinbase; in December 2017 it traded above $19,500, and in January 2019, it traded below $3,350.
Still, Dorsey is a supporter of both bitcoin and the broader idea of an Internet-based currency.
Dorsey's payment processing company Square is working to ready itself and the community for what Dorsey considers the eventual future: digital currency going mainstream.
For example, Square is hiring five engineers to work entirely on making the crypto ecosystem better," Dorsey told the Australian Financial Review. "I think the internet will have a native currency and anything we can do to make that happen we'll do."
Further, when bitcoin becomes ubiquitous, as Dorsey predicts, Square will focus more on building services to support it. "It'll be things like hardware, analytics and payroll and lending," Dorsey said.
In February, Dorsey tweeted that he himself exclusively owns bitcoin (of the bevy of cryptocurrencies available).
"Bitcoin is resilient. Bitcoin is principled. Bitcoin is native to internet ideals. And it's a great brand," he tweeted.
Dorsey prefers bitcoin for its longevity, among other reasons, he told The Sydney Morning Herald for a story which also published Thursday.
"I think [bitcoin's] the best bet because it's been the most resilient, it's around for 10 years, it has a great brand and it's been tested a bunch," he said.
"As I look at all cryptocurrencies that could fill that role of being the native currency for the internet, [bitcoin is] a pretty high probability."
In March, 2018, Dorsey said it would roughly a decade before bitcoin would become the global currency.
"The world ultimately will have a single currency, the internet will have a single currency. I personally believe that it will be bitcoin," Dorsey told The Times of London at the time. It would happen "probably over ten years, but it could go faster."
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