This effect occurs when a small change in input leads to large changes in output. This is essential to ensure greater safety. Since it is much more difficult to predict what Input was, even when knowing the output.

If a single bit of the input leads to only one bit of the output, it is easy to try to find the input: just change a bit of it and check if it is correct.

It's like the butterfly effect. A small change leads to unexpected results.

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