it's because the market is in a heavy speculation phase, when will be in a heavy adoption phase with a very big market cap the price will be more stable for a long time
this does not mean that swings will not happen(gold for example still has its instability phase despite 6T marketcap), but at least you will not see +50% in 3 days or something
what you said is ok but at last you said we will not see +50% in 3 days how can it be , last month withing 3 days it went above 100%, so it is clear that the market statistics are unpredictable.