is that we get to keep watching the same characters episode after episode. We get to see them grow and change and form relationships and achieve their dreams, all while telling compelling stories week by week. Unless, of course, aSometimes, actors leave projects because they want to work on other things or their stories come to an end or their contracts simply come to an end. The practical or logical reasons behind the scenes don't necessarily make losing a character any easier, though.
One of the shows that has experienced many a cast shakeup is Grey's Anatomy, which has been running since 2005 and undergone several character changes over the years. Others include The Walking Dead, now in its 10th season, and long-running series like Law & Order: SVU, and NCIS. But even some shorter shows have gone through major changes, like The Affair — which is in its fifth season — and the MacGyver reboot, which is only in its third season.