As like human or animal migration, software migration is the shifting from one environment to another new environment aiming to hold better standing. A newer software version usually brings new advantages and functionalities. Software migration comprises the benefits of the new features & functionalities, keeping old settings unaffected or little alterations, and safeguarding the application performance in the new environment. Software migration, specially SharePoint & Office 365 migration are labor intensive and associated with risk factors. If not done in right ways, consequence will be a real drainage of time and resources.
A ruined migration may leave you with unworkable application...