I do agree with you 100%. As important as client engagement is, especially for the purpose of feedback, if you can extend client engagement past the sales conversion phase, you stand a better chance of holding on to your client.
After-sales services, such as surveys, product onboarding, maintenance, and routine checks, are vital after a successful sale to ensure the longevity of the business. It is the follow-up through after-sales service that enables you to have a long-term client throughout the duration of your business.