The channel survey is a great place to ask broad questions that every subscriber to your channel will be required to answer; in order to support your webinar program or lead generation campaign.
Some examples are: agreeing to specific terms and conditions, zip code, street address, and other qualifying questions. A subscriber to your channel only has to answer these questions once to view all of your webinars.
The webinar survey is configured per webinar. This survey is intended to ask questions which are unique to this webinar, or are in addition to your channel survey. A common reason to use the webinar survey is when you have a sponsor or co-presenter at your webinar who needs specific information from the audience that you do not normally require.