If you look at it as Currency, it is difficult for an average person to understand it because it is different.
Bitcoin, being a different kind of a digital currency, it breaks down conventional thinking in many aspects. No central regulatory body. The concept of mining. The open-ledger (blockchain), the way miners are rewarded, how transporting value is determined by its packet size and not value, the hash rate, the concept of limited supply. The 100 Million pennies in a Bitcoin, etc.
Its difficult enough for people in the money space to thoroughly understand Bitcoin (we all say we understand it, but do we really?).
For a common person, its an overkill. Its like trying to explain the concept of TCP/IP, Networking, Routing, the Internet for someone who wants to use email. Overkill.
This is very true. And this is most probably be one of the primary reasons why a lot of people all over the world do not immediately buy the use of Bitcoin. Sometimes, Bitcoin is actually perceived as something that only belongs to the geeks and the techy and the nerds and those that are always updated on the world of technology whether it is related to finance or gadgets or something else. There is no easy and straightforward learning and use when it comes to Bitcoin.