In 1984, why does Winston Smith hesitate to write in his diary?
In the opening chapter of 1984, Winston is very hesitant to write in his diary for two reasons. Firstly, while it is not illegal to own a diary in Oceania, Winston risks a significant punishment if it is ever discovered by the Party. It is "reasonably certain" that he might be killed, for instance, or that he would spend at least 25 years in a "forced labour camp." His fear of being detected by the Party is, therefore, a strong factor in his hesitation to write.
Secondly, Winston hesitates because he does not know what to write. While he has prepared for this moment for some time, he is seized at the last minute with a kind of stage fright:
For some time he sat gazing stupidly at the paper.
In Winston's world, self-expression is discouraged and actively rooted out by the Thought Police. For Winston, then, having the opportunity to express himself on paper is so unusual that it causes him to hesitate.