I see two reasons why one might want to do it: 1) If someone breaks into your account, that person can steal all your search history. This is why I disabled se

I see two reasons why one might want to do it: 1) If someone breaks into your account, that person can steal all your search history. This is why I disabled search history recording a long time ago. 2) It was uncovered that Google passess some of its data about users to third parties, especially ads agencies. Now, with the new policy, you can't be sure that search data leakage will not occur. Moreover, ads agencies use mechanisms like cookie syncing to share user data between themselves.