According to Woerkum, v., C, Aarts, N., & Herzele, v., A. (2011) unplanned change usually occurs because of a major, sudden surprise to the organization, which causes its members to respond in a highly reactive and disorganized fashion. What are your thoughts?
Reference
Woerkum, V., C, Aarts, N., & Herzele, V., A. (2011). Changed planning for planned and unplanned change. Planning Theory, 10(2), 57-72.