I noticed that the price of Bitcoin change much like all altcoins.
But the price of other traditional currencies like the euro, for example, are stable and do not change much.
Because Bitcoin is mostly used as a vehicle for speculation, not as a means of exchange (unlike traditional currencies)
Honestly Bitcoin's market capitalization is very small (at about US $14 Billion) when compared to the large amount of fiat currency notes in circulation. This often leads to higher volatility cause bigger whales can infuse and dump a lot of cash causing the price fluctuations. There was this large infographic somewhere online that showed how small Bitcoin's market cap was compared to other currencies that show stable values when compared to Bitcoin's price
Bitcoin may be tiny when compared with the US dollar or Euro (and other major currencies out there)
But even with this market cap Bitcoin is in the upper half of the list of all countries if we ordered them by the amount of money in circulation (in dollar terms). The problem is the Bitcoin market cap is utterly misleading itself since only a minor part of all bitcoins mined so far gets actually circulated (traded or used as a currency and casino chips), The rest is stashed away and doesn't circulate. Indeed, that makes the price higher, though it can be detrimental to Bitcoin in the long run