To have the native functionality of being able to validate on a string or pattern that needs to appear on the page being rendered.
The purpose of this is to validate that the "correct" page is rendering. and not an error page with a "200" ok response code.
This can be done today by creating a selenium script. but this is another step that needs to be manged and maintained. and a native setting in the setup of the check would make this process simpler and quicker. both internally and externally.
We recommend users to use selenium scripts that verifies patterns on the page. As long as you keep the number of selenium actions to a minimum, it will decrease the amount of time spent on maintenence.