I personally think that it all depends on the Situation and Market Scenario at a particular point in time. If you are new to the market then it will take some time to digest these things because it's practical and cannot be explained by someone. For example, if you consider last week then you would see that from last weeks Bitcoin is falling and at that time there were altcoins which were falling along with bitcoin and also there were few coins who were beating the bitcoin in terms of price, Volatility, and demand that means it all depends on the market strength and scenario and according to that Bitcoin price movements reacts towards the Altcoins.