Why was a debt flag process introduced?

The CRU (Commission for Regulation of Utilities) introduced a debt flagging process to discourage customers from switching energy suppliers without first paying current arrears on their existing energy bill. This process is known as "debt hopping" which has a significant impact on customers. It is considered to raise costs for energy suppliers, and consequently for all consumers, and further compounds an individual's debt situation making it more difficult to manage in the long run.