Whatever the case, if the web form design creates a bad user experience, this can create several a cognitive barriers for the user. Which makes the following question - and answer very relevant: "When it comes to Web Form Design mistakes not to make, what UX advice or suggestions would you give the help a designer or developer?"
Interviews of individuals is not suited for medium to larger groups of people. It's not an effective use and if would take too long to gather the data. That being said, I've used many different techniques to help speed up my UX process and utilised methods that help retain flexibility. Here are just a few that you may already be using in your day to day UX role.