Dread and Breakdown.
In many, or most, online forms, a red asterisk is used to signify that a field is mandatory, and that the form will refuse to submit if it does not have information entered in it.
On long forms, this can be rather difficult, since someone can enter a lot of information, only to be stopped by a field requesting the phone number of a high school guidance counselor. Also, sometimes forms will not allow foreign addresses or phone numbers to be entered, while requiring the information. In general, the red asterisk is a great way to bring the flow of information to a grinding, miserable halt, often based on asking for irrelevant or unavailable information.
Bonus points if the web page requires all information to be entered again, although to be honest, I haven't seen that bit of fuckery for a while.