We're All People
A recent study (www.McKinsey.com) by a consulting firm took 3,199 executives as subjects from all over the world and found out that only one-third of change projects or organizational transformations have been a success. This is due to the human factor that enters into any kind of pursuit for change and the unreasonable aspect of human conduct.
When process changes, technology changes, or team changes come to bear in the work setting, the counter-intuitive conduct of team members can cause them to misinterpret changes and exhibit less-than-optimal behavior.
Another study by Hiatt and Creasy discovered that the top barriers to change management in a project are employee resistance, pitiable executive sponsorship, middle-management resistance, inadequate resources, and corporate political views. Except for limited resources, those four barriers are related to humans. However, if people or humans were not an issue, limited resources would also not be a major issue either. For example, if humans were approachable to change, it would not be difficult to gather talent, time, and knowledge.
Human change may be the most common obstacle, but by managing it effectively you can minimize negative impacts.