Before we get to the final part of my look at replayability in video games, there is one element we need to discuss first. Whenever a game must create something new for the player to experience, it all comes down to procedural or random generation and both elements are essential to understand about replayability.
A major evolution of game development over the years would have to be the use of procedural generation. Instead of having a linear experience that is one-and-done, you can create something that always keeps the player guessing. Rogue-likes, survival and simulator games have been using procedural generation to extend their replayability.
When it works, you have a game with almost unlimited replayability. However, as with all elements of game design, it’s not perfect and can hurt as much as help a game if not properly balanced.