Reasons for deferring the delimitation exercise and nullifying the final order:
- Four States: The government deferred the delimitation exercise in four states - Assam, Manipur, Arunachal Pradesh, and Nagaland - due to various reasons such as ongoing insurgency, internal disturbances, and lack of adequate data. These states have special provisions under Article 371 of the Constitution which necessitated a careful approach to the delimitation exercise.
- Jharkhand: The final order for Jharkhand was nullified due to discrepancies in the data used for delimitation, leading to concerns over the accuracy and fairness of the exercise. It was deemed necessary to review the delimitation process in Jharkhand to ensure that it reflects the true demographics and boundaries of the constituencies.

Binding nature of delimitation commission's orders:
- The orders of the Delimitation Commission are binding on the government as per the Delimitation Act, 2002. The commission is an independent body responsible for determining the boundaries of parliamentary and assembly constituencies based on the latest census data.
- Once the Delimitation Commission issues its final order, it is expected to be implemented by the government without any alterations or modifications. However, in exceptional circumstances where there are valid concerns regarding the accuracy or fairness of the delimitation exercise, the government may choose to defer or nullify the final order.
In conclusion, the decision to defer the delimitation exercise in four states and nullify the final order for Jharkhand was taken to address specific challenges and ensure that the process is conducted accurately and fairly. While the orders of the Delimitation Commission are generally binding, the government has the authority to make necessary adjustments in exceptional cases to uphold the principles of democracy and representation.