Probably because you don't understand the concept of inflation. Inflation is only marginally related to the number of currency units in circulation, much debate about that supposed connection and the jury's still way out. Inflation is the loss of buying power of a currency, and BTC has lost 50% of its buying power over the last three months, a "spectacular" run of inflation. You'll note that nothing is valued or priced in Bitcoin...its just too volatile to be a measure of value, or a store of value. Possibly some day BTC promoters and "hodlers" will quit trying to profit from possession of the "coins" and start using them as their inventor intended...as a currency. At that point their value will stabilize and we will be able to test whether they grant any advantage over fiat currencies, which at this point are far easier to use, far less risky to hold, and far more friendly to the planet.