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.
Wasteland (1988) → Wasteland 2 (2013)
Why? Brian Fargo, who had previously worked on the popular 1988 RPG, unsuccessfully attempted to pitch a sequel to publishers several times. In 2003, Fargo's company InXile acquired the rights to the franchise and, after a sole announcement of their intent to develop a sequel in 2007, Wasteland 2 was ultimately crowdfunded through Kickstarter in 2012. It is slated to come out in 2013.
What else took this long? The Serbian Empire's rule lasted twenty-five years.
Kid Icarus: Of Myths and Monsters (1991) → Kid Icarus: Uprising (2012)
Why? After the release of a single sequel to the 1987 platformer Kid Icarus in 1991, the franchise went quiet. Its main character, Pit, appeared elsewhere—most notably in the 2008 crossover fighting game Super Smash Bros. Brawl—but there was no word of a new game until the announcement of Uprising, which came out in 2012.
What else took this long? The creation of Brahms' Symphony No. 1 took twenty-one years from start to finish.
Duke Nukem 3D (1996) → Duke Nukem Forever (2011)
Why? The follow-up to the 1996 first-person shooter had a difficult journey. In fifteen years, Duke Nukem Forever switched game engines several times, its development studio 3D Realms got in legal trouble with then-publisher Take-Two because of the delays, and its original development team was laid off due to downsizing. In the end, Gearbox Software swooped in to help finish Forever, buying the franchise rights from 3D Realms and working with the last few remaining developers to release the game in 2011.
What else took this long? A whole lot of things.
Diablo II (2000) → Diablo III (2012)
Why? Hack and slash RPG Diablo III had already been under development for six years when it was announced in 2006, with a lot internal debate about the game's direction slowing down actual development. The closure of Blizzard North, the team responsible for the first two games, also contributed to the delays. Later, DIII underwent several art style revisions before it ended up with its final look, finally getting released in 2012.
What else took this long? Roosevelt's presidency lasted twelve years.
Fallout 2 (1998) → Fallout 3 (2008)
Why? Interplay Studios, the original publisher of post-apocalyptic RPGs Fallout 1 and 2, went bankrupt and closed the studio working on the sequel, Black Isle. The rights for the sequel were sold to Bethesda Softworks, who only began developing the game once they've finished all work related to another project of theirs, The Elder Scrolls IV: Oblivion. In the end, Bethesda decided to develop Fallout 3 from scratch, abandoning Black Isle's work completely, creating a hybrid first-person shooter/RPG instead.
What else took this long? All seven Harry Potter books were released in the span of ten years.
Deus Ex: Invisible War (2003) → Deus Ex: Human Revolution (2011)
Why? In 2005, Deus Ex designers Warren Spector and Harvey Smith left Ion Storm, the studio behind the first two entries to the shooter/RPG franchise. Ion Storm was then shuttered, and Eidos Montreal eventually took over development of the sequel. After a 2007 announcement, Human Revolution was released in 2011.
What else took this long? Jean-Claude Van Damme's career in martial arts ended after eight years.