Like changing for the sake of change, assessing for the sake of assessing has some major downsides. Meaningful assessment can take many forms (try a search for meaningful assessment), but it should always have one outcome: improved opportunity to for students to learn.
This from a recent post on the Rational Mathematics Education blog: “Creating ANY good test item is challenging, but creating test items that actually tell us what we need to know to improve teaching, learning, and parenting when it comes to academic subjects is a major challenge.”
Ask Kermit. It’s not easy being green. And it’s not easy to write a good assessment that gives meaningful data.