The Metal Gear Solid series always had a quite extensive degree of replayability, especially if one wanted to get certain emblems and achievements, but what about Metal Gear Solid V: The Phantom Pain?  Hideo Kojima is still working on creating quite a lot of replayable elements to enhance the longevity of the game, as he explained in an interview on the Japanese site Inside Games.

In some missions there are "No Kill, No Alert" challenges, and all those challenges are connected by social [rankings] and can be played any number of times. In addition to that, even in the same mission there will be different situations, like different ways to attack and different weather conditions.

Everything you do will eventually be evaluated at the base. For example, if you bring back the wrong target in a hostage rescue and you should do it again to improve your result. That's the (non-linear) replay value due to the freedom enhanced by an open world.

Looks like Metal Gear Solid V will keep us busy for quite the long time, and the fans of the "No Kill, No Alert" playstyle will have something to match their skills against. Considering that the enemy soldiers looked a lot less predictable in the demos showcased at Tokyo Game Show, it's probably going to be quite hard to complete our infiltrations without being spotted at all.