In order to make scans run as fast as possible, the Quick Scan is not as comprehensive as a regular scan. Here are the main limitations:

• Since we do not crawl the web page, we are unable to check if links on the page are working and therefore do not give a report for broken links and images. If you wish to get a broken links report for a single page, please use the Single-Page Scan feature instead.
• Not all checks make sense in the scope of a single page scan. Some checks that are run in regular domain scans are excluded from the Quick Scan. 
  For more information, see the FAQ article: 
  Which checks does a Quick Scan include?
• Quick Scan results are not synchronized to your regular Acquia Optimize scan results. The results of a Quick Scan will not show any longer after you have navigated away from the current page or refresh your browser. If you wish to run a scan of a single page and ensure that results are synced to your existing scan data in Acquia Optimize, use the Single-Page Scan feature instead.
• If we detect that the page you are trying to scan is larger than 20 MB, the scan will stop and you will see the message “The page is too big for Quick Scan”.

For instructions on how to do a quick scan, see the user guide articles:

• Single-page scans

• Quick Scan.