Adjudicator on 08 November 2009
There's nothing to explain. If I plan to sell 100 million pies, I can set selling 50 million pies as a milestone or 10 million pies as a milestone. It is done often in project management to asses your progress in a time period.
Whether or not you think it is anything special is irrelevant, all i am saying is that the word milestone is an acceptable term in the context of the OP.
