Mr. G Taro
This is Kawaguchi Hidetoshi. This is my humble answer to the question.
It is truly precious and thankful that you can practice Buddhism.
“Are there any other reasons why Buddha's teachings are difficult to convey?” ... Yes, there is.
There is an episode about this in After Shakuson Seido. This is an event called the “Bonten Solicitation.”
It is said that Shakyamuni, who attained enlightenment under the Bodhi tree, quietly rejoiced in the state of nirvana, continued to meditate even deeper, and thought about completely freeing himself from this world so that he would no longer be born and reappeared in a world of confusion and suffering.
Also, it is said that they hesitated to preach this profound teaching because they thought that no one would understand it, even if they explained this profound teaching to lead to nirvana.
It is reported that when Shakyamuni was hesitating to be taught in this way, Bonten appeared and was recommended three times, saying, “Please explain the path leading to that wonderful nirvana to sentient beings and save sentient beings from loss and suffering.”
In response to this invitation from Bonten, Shakyamuni, along with his merciful will, decided to preach the path leading to nirvana to sentient beings, and Buddhism finally begins.
What you can think of as one of the true intentions of Shakyamuni being hesitated to preach his teachings is that Buddhism is an alternative theory, a teaching that uses convenience, and it is explained according to the root of the person being preached (according to the ability to be understood), and there are also general teachings that do not hold up in a sense. Therefore, I think it was thought that the teachings preached to one person could be applied to another person would be extremely difficult, and on the contrary, caused misunderstandings and confusion, and might not be beneficial.
Of course, representative teachings such as the Four Law Signs, Sky, and Good Luck can be listed as general, but even so, there are considerable differences and scope widening in interpretation. Even though it is difficult to decide as a unified opinion, it is probably because of the above reasons.
As for the feeling that is difficult to convey, in the end, it is due to the lack of ability and convenience of a poor student to identify machine roots, and I am really sorry every day.
Kawaguchi Hidetoshi Gassho