Some language acquisition software I’ve seen emphasize comprehension as the driving force of language learning. This approach focuses on learning to process messages in the target language, heralding the importance of understanding words and phrases before using them yourself.
Memorizing endless amounts of phrases? Forget about it. In comprehension-driven learning, you work on comprehending the message each phrase is trying to convey. The idea is that if you can grasp what’s being said, the speaking will eventually emerge all on its own.
The most extreme example of this approach is full immersion. Drop yourself in a foreign land where everyone speaks the language, except you. Little by little, you’ll begin understanding their communication through observation. Once you gain a good facility for figuring it out, you can’t help but be able to converse yourself as well.
In comprehension-driven language learning, acquisition is believed to be a developmental process. First you must learn to receive input (lots and lots of it), then you can competently give your own. Your brain works to analyze language naturally, slowly giving you the facility to use what you’re absorbing from your environment.
What about memorized material? Under this concept, it does nothing but give a false impression of proficiency. If you work on comprehension first, your speaking becomes more ingrained, such that it will develop into a skill you can count on, rather than forget after a brief period of inactivity.