Because, by design, there will never be more than 21 million Bitcoins in existence. And thanks to hoarding and attrition, we can be sure that it will eventually serve as nothing more than as a collector’s item. . . . I would like to call upon the Bitcoin community to stop referring to it as a digital currency. This is misleading and harmful.
WHY BITCOIN WILL FAIL AS A CURRENCY
Distributed Systems Engineer
Source: Tav's Blog