Direct Debit is protected by the Direct Debit Guarantee, which is backed by the UK's banks and building societies.
For your customers
They are notified before every payment. If a payment is taken in error, they get a full, immediate refund from their bank. No questions asked. They can cancel at any time.
For your business
Payments are collected automatically. No chasing. Mandates are legally binding authorisations. Collections are processed through BACS, the UK's secure payment clearing system. All Direct Debit providers must pass rigorous vetting before they can process payments.
No other payment method offers this level of protection for both sides.