set a target

To set a target is to fix the result you mean to reach. A number on a whiteboard, a date beside it, everybody now measured against both.

It takes for and of: set a target for recycling, a target of forty per cent. Set is the fixing verb — you set a date, a price, an alarm — and the thing set is meant to stay put, which is why moving the goalposts is such a common complaint. Hit or meet one is success, miss one is not, and an ambitious one is the polite way of saying nobody believes it.