If you refresh the web service connectors, Designer recreates the connector services using the existing WSD, without making any changes to the WSD, so it uses the copy of the WSDL stored in the WSD.
If you refresh the WSD, Designer rereads the WSDL from the source(a file, the service provider’s URL, etc), so any updates made to the WSDL since the WSD was originally created can be incorporated.
#Integration-Server-and-ESB#webMethods