Motivation

I am of the opinion that most people don't need to learn a second language; not that there are no advantages to doing so, but so many people tell themselves they need to learn Spanish, Chinese, or something relevant to their area and fail to make any meaningful progress as a result. If I just described you, I would seriously advise you to reconsider your life choices. Language learning is a lifestyle, not a necessity; most people aren't able to remain consistent if they feel they have an obligation to learn. I love language learning, it's what gets me up in the morning and continuing to breathe air when the other things in my life are falling apart.

While I believe there's a moral obligation to learn the language of the locals of a given area if, for example, you've moved to a different country, even this isn't adequate motivation for most people. I've heard plenty of stories of people moving to Japan and, rather than actually learning Japanese, end up finding an English speaking enclave and never make any real progress. I've witnessed a similar phenomenon first hand, as my own neighborhood has, within the past 15 years, slowly turned into a sort of Lil El Salvador, most of my neighbors don't speak English to any meaningful extent. They have created a Spanish enclave in my own hometown, which, despite me finding it morally irritating, is proof that becoming fluent in the dominant language is not actually necessary; you can get along just fine without doing so.

In short, don't take this path for anyone else, do it for yourself, because you want to learn for its own sake.