I can be devil's advocate here, and I think it's a factor in a bunch of slow games that are too complex for their creator, their platform or both to handle: variables in text games can be painful.
You can write some great stuff, but then it feels nearly empty upon realizing that "well this character would say this word instead, if this variable is that value." Or, a whole conversation might never happen if a variable is a certain value. For some people, they just move on and don't worry about it. It keeps others awake at night, especially when we consider how choices can expand into vast numbers of possibilities that differ in many ways ranging from subtle to extreme.
One might ask, how can someone not worry about it? Well look at Interplay. They wrote some good text games, but they were by no means perfect. The point being: you want to have impact, not be perfect. As flawed humans, it is unlikely that we will ever produce a perfect product. We can make a fun and interesting product that is good enough that people will ignore or dismiss the imperfections.
If we want to give the player the reality of choice, and not just some sliders and radio buttons that do nothing, then these things are tough to handle when not managed properly. To me, it means, when a.i. starts to write text games well, it will completely outclass humans. It's not there yet, but it will be probably within most of our lifetimes.
