Feature Inquiries : select the associated landing page you'd like to report on

I'm inquiring about something I'm curious about while setting up an email campaign.

If you check the attached file, I wonder what the exact purpose of the red checked part is.

From the perspective of the campaign, it is a function to call up the form and landing page related to the e-mail.

What are the benefits of using this feature to automatically place form and landing pages in your campaign?