1. change the rules in an ongoing situation
move/shift the goalposts by suddenly changing your demands
If someone ‘moves the goalposts’ or ‘shifts the goalposts’, it means they change the requirements, objectives or criteria in a way that often makes things more difficult for someone else or in order to gain an advantage. When you ‘shift the goalposts’ the implication is that the changes are unjust or unfair or different to what was originally agreed. This is a phrase you will hear in social and professional contexts. Similar in meaning to ‘raise the bar’.