The Kia Optima is so last year. For its 2021 redesign, it gets a new look and a new name: the K5. “K5” is the South Korean naming convention for the Optima, so it’s safe to say that this mid-size sedan isn’t going away so much as it’s moving on. The K5 redesign also takes on a different look compared to Optimas of the past; it’s a little longer and more swept back than previous iterations.