A criterion is a standard for judging something. If you are holding a cupcake competition, your number one criterion might be the smoothness of frosting.
A criterion is a category for judging, but can also be a prerequisite for an achievement. It might be an application requirement for a teaching job that you have taught already for two years. If you haven’t, then we say you haven’t "met the criterion" for job experience. Likewise, if you establish the model for something, say you deliver an exciting, profound graduation speech, we might say you "set the criterion" for future speakers.