There are times when we don't want to allow a user to submit a form if certain field values exist (for example a minimum age requirement is not met). Please include visibility rules for the Submit button!
Really easy to do this with a little Forms 2.0 JS.
I'd consider, though, the user experience of having nothing at all happen if, say, a dropdown is clicked "incorrectly." If I encountered that, I'd figure the form was broken, not that I didn't qualify: we're still used to either [a] visual feedback about the auto-submit of a form/form field or [b] a manual submit button. Although I guess if you don't care what the invalid leads think....
Sanford Whiteman: It's not a bad idea, but it is a bad user experience to manage it that way, and we'd rather not accumulate junk data in the system. As to the JS, certainly that's true, but I can't imagine it would be terribly difficult to include visibility rules for the submit button just as easily as for other fields in a form. Hopefully Marketo agrees.
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