The phrase "unwelcome change" refers to a situation or shift that is undesirable or not wanted by someone. It suggests that the change is seen as negative or unwelcome by the person experiencing it. Full definition
Developmental Milestones Developmental milestones are wonderful moments in child development but they can also bring unwelcome changes in behavior. (sleepinglittledreamers.com)
A new year has just begun, and for the staff and boys of the School, a wind of unwelcome change is blowing. (bookbrowse.com)
Her novel Q Road investigates the lives of a rural community where development pressures are bringing unwelcome change in the character of the land. (bookbrowse.com)