Why Avoid Missing and Error Requests

Missing requests and error requests are requests that the browser makes for assets that fail completely with or without an error message. These requests usually indicate a problem with the particular asset that the browser is trying to access or a problem with the service hosting the asset. It is extremely important to investigate and resolve these issues because failed requests for important assets like CSS, JavaScript, or other information required for properly loading can cause the web page to not load correctly or function as expected for visitors.

Troubleshooting missing and error requests can require advanced web page debugging skills. Most browsers’ developer tools have a network request analyzer that will highlight requests that do not complete or return an error message. The network request analyzer should be the first place to check for missing and error requests.