“One reference is good enough!”
There’s an old saying in the reference-checking business that goes something like this: “More information is always better than less.” Checking one reference is never good enough. The idea behind careful reference checking is to look for consistency among the comments made by multiple references. It’s pretty tough to find consistency in the comments of only one reference, not to mention the increased possibility that the comments from only one reference will be slanted in one direction or the other. The validity of reference checking can only come from talking to, typically, three references. That’s how you compare and contrast comments and explore inconsistencies…and that’s how you make a more informed hiring decision.