1, Don't War Einstein was a very great physicist, and the main basis and theory of modern physics came from the theory of relativity. Relativity includes many things, among which atomic bomb and nuclear energy are related. As a peace-loving man, he hoped that the atomic bomb would end the war. However, the appearance of the atomic bomb made the war more and more cruel. In particular, the fact that the United States dropped an atomic bomb on Japan dealt a great blow to Einstein. He knows the harm of the atomic bomb and that it will cause great casualties. And he burned all his notes before he died, probably because he didn't want a war or disaster like an atomic bomb.
2. There may be mistakes. Some scientists think that Einstein burned all his notes before he died. Maybe he suddenly found that there were many wrong data in his notes. And the error of one data leads to the error of the following data. In order to prevent future generations from using their own wrong data, they simply burn them all. Personally, I feel that this statement is not particularly reliable. It is possible for people to make mistakes, but it seems unreasonable to find out that something has gone wrong in a certain step before dying. If you have the ability to know mistakes and burn them, you only need to tell future generations about them, and there is no need to burn them all.
There are some things that people don't want to study. There is also a conspiracy theory that Einstein's notes record many mysterious things. For example, the ultimate of the universe, the method of traveling through time and space, the record of exceeding the speed of light and so on. He was afraid that humans would make changes with these things and simply burned his notes.