A foreign language can be learned in a number of ways. Some people argue that learning the language while living in that foreign country is the best way. In my humble opinion, I partly agree with this view as there are also better ways to study another language.
On the one hand, there are many benefits for learning a foreign language in the country where it is spoken. First of all, learners do not need much effort to be proficient in speaking because they have full exposure to that language through daily conversations. For example, if someone, who lives in an English speaking country like the USA, can speak English without learning a lot. In addition to this, the time taken for learning a foreign language is obviously shorter than regular learners since they have full language immersion. As a result, their speaking and listening skills improve quickly, and they can learn slang, idioms, and culture naturally.
On the other hand, there are some methods as useful as living abroad for learning another language, such as teaching with an experienced tutor or self-studying with online tools. First and foremost, studying with teachers can be motivated to learn, and it allows us to study all 4 skills systematically with structured lessons and well-organized courses. On top of that, online tools for language learning, such as Hello Talk, Wakie, and similar apps can provide conversations with other learners around the world. Therefore, learners can self-study with those apps without spending a lot of money like living overseas. These approaches are viable options for those who cannot go abroad.
To sum up, I firmly believe that although learning a new language in that foreign country is advantageous, other means of learning are good as well.