Though I might be wrong on this but I think the main or the core reason of creating bitcoin was to use it to trade p2p which is to buy goods and services online but that part or function of bitcoin creation is not working perfectly yet and I don't know if it will work in the nearest future. Because everyone one is going into the investment aspect of it and not the goods and services function. As for me the most interesting part of bitcoin is the part you can use it to buy something like Laszlo Hanyecz who used bitcoin to buy Pizza.
I like to do that but no store in my area is accepting bitcoin in fact they don't even know the name. And those who use exchange to buy bitcoin because it is the fastest way to acquire bitcoin.
The reason why bitcoin was created is not just for p2p or for buying goods and services. Bitcoin was created for freedom, for people to handle their money without going through stress like how we stress ourselves to get our money back from the bank. Bitcoin was also created to gain better financial height because the traditional currency have no value. Bitcoin is here to add value to the money that we have .