There are two modes of learning languages, depending on the requirements, viz: Quick learning and Deep learning. Let me explain further!
When you are a busy individual looking to achieve something at short notice (eg: IELTS or ESOL etc.), the best thing to do would be to go for the Quick learning mode. In this mode you select courses that are structured in a way to provide you with fast training in any one specialized section of a subject. In Quick learning mode you absorb a lot of information and retain them in your mind for a short duration, i.e. until the test is over or the goal is achieved. Once you have achieved your target, there is usually no need for further retention of the subject knowledge. Once you get a good score in IELTS, you do not need to remember the training methods or tricks and tips any more. This can be done by joining a short term course of 10, 20 or 30 lessons usually, depending on your current proficiency.
When you are an individual with sufficient free time and a deep thirst for learning a subject to its core, you should select the Deep learning mode. This mode is suited for attaining excellence in any field. In this mode, you are not in a hurry to reach any target. You keep exploring the subject at your own pace and learn and retain as much as you can or want to. The information and knowledge gained through this mode is for long-term retention and prepares you to face all situations pertaining to the subject. You will never be surprised by a test as you would have eloquent knowledge in it through long-term practice. For this mode we usually do not fix a time limit as each person's learning and retaining speed is different. Carry on learning until you are satisfied with your progress.
In the Quick learning mode you have to work very hard for a short time and it might be exhausting. Results are not guaranteed! In the Deep learning mode you may either learn comfortably or you may work hard. You may choose to exhaust yourself with a lot of lessons and homework or you may learn in a relaxed way and learn with fun without any stress at all. It is very flexible. However, very deep knowledge of a subject, achieved through Deep learning, usually guarantees your success and gives you an unbreakable confidence, no matter where you are.
The choice will depend primarily on the amount of time available and the depth to which you wish to delve. Choose your mode and start learning today and remember, there is no end to learning :) Cheers!