After twenty-one years, The Legend of Zelda: A Link to the Past is getting a direct sequel. That's quite the gap, twenty-one years. But it's far from being the only big gap.
Game development takes a long time, and during that time, a great number of things can go wrong. Licensing issues get in the way, publishers disappear and people quit. Sometimes, a franchise simply loses its momentum, and has to wait for someone to pick it up. Link to the Past 2 is but one of many examples of slow-to-arrive sequels. Let's have a look at a few others.