What should an architect recommend to make sure that users that gained access to a...

For custom objects, a dedicated Apex Sharing Reason should be used when programmatic shares must survive a change of record owner. Apex-managed shares that use a custom sharing reason are designed to represent access granted by business logic independently of ownership. A share created with RowCause Manual is different: manual shares can be removed when ownership changes, so they are not reliable for persistent application-managed access. The with sharing keyword also does not control the persistence of share-table rows; it controls whether Apex respects the current record-sharing model when executing queries and DML. A custom sharing reason has an additional operational advantage because it gives the application a stable way to identify, update, or remove only the shares created for that business process. Study Guide reference: Access to Records - Apex-managed sharing, Apex Sharing Reasons, RowCause, ownership changes, and custom-object share lifecycle. The implementation should also be validated with representative users so effective permissions, sharing inheritance, and any cross-object access behave exactly as designed before production release.