If your verification fails it means the verification agency is unable to verify the information you provided. This can be due to a number of factors. The agency may not have its services available at the moment or may not have enough information on file to verify your information. A failure can be caused by a number of reasons and is not recorded on your profile. A verification failure does not mean you did something wrong. Usually, you have a choice of other agencies to request the same verification from.
Failed verifications do not show up on your profile and nobody will know if you failed to verify certain information. Only successful verifications, later reviewed and approved by you, will be added to your identity. While verified data will be private to you, the evidence of performed verification may be visible on your profile. You always have the option of making your profile completely private and only reveal your private information upon request.