Specifies whether to cache the result of ZK WCS files (the stylesheets of components) at the server. By default, it is enabled. It means the Stylesheet specified in a WCS file is loaded and cached at the server. The performance is good. However, if you are debugging the widget styling and you'd like to modify the content without restarting the server, you could disable the caching of WCS files.
Notice that you don't have to turn it off if you restart the server each time you modify the widget's css files.