Character questionnaires ask inane questions - a character’s favorite color or what they have in their refrigerator. These questionnaires are superficial and cosmetic and do not create characters that walk off the page and into reader’s hearts.
Readers want to connect with the character’s inner workings. They want to empathize with the protagonist’s feelings. What is their inner conflict? What are their fears? What secrets does the main character keep so hidden that even they do not acknowledge their shameful existence?
In order to face whatever conflict the author throws at them in the story, they must be armed with more than their favorite color or the contents of their refrigerator.
It is only when the author builds characters from the inside out that he can costume them with the kind of frippery found in questionnaires. It is only then that the inanity of the questionnaire becomes integral to the story.
For example, a female protagonist neglected as a child by her alcoholic parents and who had to fend for herself and them would probably be ashamed and hate her childhood. She would overcompensate for her childhood helplessness by being in charge and in control of everything in her adult life. She might yearn for love and attention, yet keeps everyone at arm’s length.
Her favorite color would be red since it stands for power and pain and passion. She would keep a six pack of beer in her refrigerator which she never drinks. It is there as a hated symbol of what destroyed her life, but it is also a fearful reminder that she too has a hereditary propensity for alcohol addiction.
Remember, nothing should be merely superficial, coincidental, or cosmetic. Everything is dependent on the character’s hidden side, the inner workings, the psyche. To create strong fictional characters, the author must intentionally give them strong personality traits, either good or bad, and thereby make them realistic and believable.