Well even i can tell those reason quite clearly and in details LOL
The advantage of bitcoin is the high price. When we bug the bitcoin at low price and we can sell it at high price. The profit is huge when compare to invest this is the advantage. In short time itself we can make more profit at the same time you can hold it for long time will also give more and more profits than you invest. The disvantages is depends upon the market rate. We have to sell it at right time to get more benefits otherwise it leads to very huge loss. So always we have to keep an eye in the coinmarketcap.com to see the prices.
The high price is just even more like a side benefit and not just the main advantage. For those who understood the gospel according to satoshi pretty well, you will understand that the main idea why bitcoin came into existence was as a result of inflation, policies that affects transactions both locally and internationally, monopolies here and there with the banks doing whatever they want and these are some of the things that bitcoin really came to solve which gives it a lot of edge and advantages over fiat.
The disadvantages that some people see are just more like the characteristics and only if you want to see it as a disadvantage will it be a disadvantage.