By default, the Liberty profile defers servlet loading until a request is received for the associated web application. You can override this default behavior by specifying the web container deferServletLoad attribute to false.
The servlet specification defines the load-on-startup servlet attribute, which is specified in the web.xml file of a web application. If a servlet has a non-negative value for the load-on-startup attribute, the servlet must be loaded and initialized when the web application is deployed. The Liberty profile optimizes server start time and memory use by not starting a servlet until a request is received for the web application. You can override this deferral so that your servlets are loaded and initialized when the web application is installed, rather that waiting for the first request for the application.
<webContainer deferServletLoad="false"/>
This
setting applies to all web applications installed in the server.