Why would you learn a language? To stay determined and create long-term skills, it is beneficial to find in yourself the deeper « Why? » you do things. 
Gif by petitemimine
Of course, working on or mastering a language enables you to communicate with foreign speakers and to get around freely and independently in a new country.
I also experienced first hand that learning languages brings us and you to discover new cultures. Kind of like travelling, it is an enjoyable moment of exploration, and you gain more knowledge, to enrich yourself.
So more than a trip into unknown customs and the Unknown, by studying and practicing a language, you can work on yourself at the same time; and it becomes an inner journey.
From there, you are more aware of your limits, which helps you to be more adaptable, flexible and/or stronger depending on what a specific situation may require.
Inner limits can mean different things. One of them I believe is our bias and prejudices. If we and you are conscious of them, we/you can accept them better, and accept everything we/you are more easily. 
And maybe, if we want to, we have then more potential to become a better version of ourselves, by being more tolerant towards ourselves and others, to be able to offer more compassion to ourselves and others. 
In other words, learning a language can feel like a powerful lesson of humility.