I just received an alert email (aka lead filled out a form) with all the lead information blank. Then I went into the results tab of the campaign to try and find out and I see a bunch of "failed: required field missing". I don't understand how this lead was able to click submit and get pushed through the campaign if he/she didn't fill out any fields. How is this possible???
One way that this can happen is if you have a progressive profiling form and the lead changes their email address when submitting a subsequent form. As little as the email address will be captured in this case. I created an alert email for this situation that is sent to me and it includes the Anonymous IP address. I then search for that IP address and I can frequently find at least one other record, which I may merge with the new one if it looks like the same person, but different email addresses, or if it is two different people, I can usually update the company name and other info from the existing record with the same IP address.