As I help team after team get on the right track with their derailed projects, one characteristic rises to the top as the cause of failure: commencing coding without first obtaining proper requirements.
Poorly gathered requirements promote future change, scope creep and missed deadlines. Further, when these happen it can lead to fingerpointing, rushed development, and lack of testing.
Businesses may not know how to provide requirements…teach them. Ensure all requirements are known, and get sign-off before development proceeds.