A wordpress smtp plugin is often installed after an order confirmation, password reset or enquiry notification seems to disappear. That is understandable, but it can lead to an unhelpful promise: that changing the transport guarantees delivery. It does not. A better choice is one that gives the administrator a clear sending path, a safe way to test it and enough evidence to investigate a failure without treating every missing email as the same problem.
This guide is for the person responsible for a WordPress site that sends useful transactional messages. It explains how to compare options, what to test before relying on one and where the limits of an SMTP configuration remain.