Whereas Recital 170 mentions: “Since the objective of this Regulation, namely to ensure an equivalent level of protection of natural persons and the free flow of personal data throughout the Union, cannot be sufficiently
achieved by the Member States and can rather, by reason of the scale or effects of the action, be better
achieved at Union level, the Union may adopt measures, in accordance with the principle of subsidiarity as set out in Article 5 of the Treaty on European Union (TEU). In accordance with the principle of proportionality as set out in that Article, this Regulation does not go beyond what is necessary in order to achieve that objectiveâ€.
Subsidiarity is a principle that says that personal data can only be processed if there are no other means to achieve the objective. Therefore, the less personal data used, the less the chances of violating privacy.
Note that in the quotation in Recital 170 above, the principle of proportionality was highlighted in bold. Equally important to subsidiarity. Proportionality says that personal data must be collected according to the purpose of processing, that is proportional, and data that will not be used for the purpose should not be collected.
These two principles Subsidiarity and Proportionality are constantly charged in the EXIN exam.