We know that the very idea sounds a bit gimmicky and you probably have your reservations about it. However this is not the place for skepticism and  believe me when I tell you, this goal is easier to achieve than you think. 

The Pimsleur language courses are presented to you in increments of thirty and the units themselves are a half hour long. Before you begin the program you are assured that 100% accuracy is not your goal so it should not be your expectation. Your primary goal is to retain 80% of the material taught to you and move on to the next unit. If at the end of a lesson you are not happy with the results you are always encouraged to invest an additional 30 minutes repeating the course. If you decide to repeat the course you would have only spent one hour that day practicing your language. Imagine now that you do this everyday for 90 days consecutively no breaks included. Can you image the amount of progress you would have made if you developed a strict regiment and stuck with it? You see 90 days is not an extraordinary length of time but it's not a short amount of time either. It seems that 90 days would provide the perfect amount of time to learn the fundamentals of your target language to the point you are confident with speaking it. 

The Language Learning blog posted an article entitled "The 90 day rule: How to learn a language in 90 days" where they mention that "becoming good at something doesn’t require a tremendous amount of effort, it requires regularity, patience and discipline".  These ingredients included with the four key concepts of the Pimsleur method make for a delicious recipe called success and the preparation time is 90 days. Since we learn things through repetition and regularity we don't have to be concerned about the intensity of the lesson because we simply don't retain things the harder they get for us. We build up our skills set through regular and consistent practice and that is what makes all the difference when it comes to learning your new language.