You're putting together a marketing campaign.
You have clarity on your audience and goals. You can clearly describe who you're trying to reach, what outcomes you seek, and how you're planning to measure success.
You have a call to action. You can answer "what do you want me to DO?" concisely. You know what you want people to do AFTER that, too.
You're ready to roll, right? Time to send those emails, mail those postcards with the PURLs, place all those ads with the QR Codes, and send everyone to your gorgeous landing page or microsite!
Hold on there, killer.
Has your site passed the "Mom Test"?
Hand your mom - or your grandpa, or your Luddite cousin - your credit card. Send that person to your microsite. Watch what happens. Does she understand what you want her to do? Can he complete your desired transaction? Does she get frustrated and bail? How long does it take him? Does she break the process in the process of trying to complete the process?
Only once your campaign passes the Mom Test, from start to finish, are you ready to roll.