move the goalposts

Từ điển Oxford Advanced Learner 8th

move, etc. the ˈgoalposts idiom
(BrE, informal, disapproving)to change the rules for sth, or conditions under which it is done, so that the situation becomes more difficult for sb
•I manage to get on top of the job, and then they move the goalposts again.
Main entry: ↑goalpost_idiom