Some records we use were not filled out by our ancestors--someone else, perhaps with less knowledge answered the questions. My big break on my wife's grandmother came not from her death certificate, which was filled out by her children, but instead her SS-5 form. The grandmother filled out that form herself in the 1960s and gave a different name for her father than what her children had put on her death certificate thirty years later.
If possible, find something the person actually provided information on. It may be different!