Here's what we know:
* Disagreement with Margaret Thatcher's Government: It's widely believed that Dahl's refusal was a political statement, specifically against the Conservative government led by Margaret Thatcher. Dahl was a vocal critic of Thatcher's policies, and the O.B.E. would have been seen as an endorsement of her government.
* Opposition to British Imperialism: Some argue that Dahl's refusal was due to his personal beliefs about the British Empire. He may have felt that the O.B.E. represented a continuation of imperialistic ideals.
* Desire for Privacy: It's also possible that Dahl simply didn't want the attention and scrutiny that came with accepting such an honor. He was known to be a private person and fiercely independent.
Ultimately, the exact reason for Dahl's refusal is not clear. However, it's likely a combination of his personal beliefs, his political views, and his desire for privacy.