Bitcoin is difficult to understand due to its interdisciplinary nature and constant evolution. It combines fields such as mathematics, finance, policy, economics, games theory, energy, cryptography, and more in order to function properly. Understanding each of these fields independently can be challenging enough, but when you try to put them all together it becomes even harder. Additionally, Bitcoin is constantly evolving, meaning there are new developments and innovations every day that require constant attention. Finally, the decentralized nature of Bitcoin adds another layer of complexity since it operates independently of any central authority or government regulation. Overall, understanding Bitcoin requires a lot of dedication and effort as well as an open mind to new ideas and concepts.