There are two types of shows: Procedural vs. Serialized.
* Procedural or episodic shows are stand alone episodes. There may be arcs that connect shows. These shows have a built-in reset button which sets the show back to default. Most of Star Trek has been of this type.
* Serialized shows are a chain of connected episodes. There is no reset button. Storylines, characters, and, sometimes, settings change over the course of the series. Enterprise experimented with serialization in its third season.
The premise of Voyager was best suited for serialization; however, the show was done as a procedural.