Most foreigners who spend a significant amount of time in Japan make an effort to learn the language. Some dedicate themselves to Japanese language acquisition and attain a high level of functionality. Others struggle mightily with anything beyond the basics.
A handful have brains wired to learn languages, start at a very young age, or have a Herculean work ethic, and achieve something approximating native-level fluency. Most of us muddle through. This article is for the muddlers.
I'm no Dave Spector, but I've had modest but genuine success with Japanese despite lacking any particular knack for languages (just ask the Spanish and Hebrew teachers of my youth). While foreigners can prosper in Japan without speaking Japanese, the ability to speak, read and write well enough to express and comprehend complex thoughts in the language makes life immeasurably richer. Japanese is trulythe gift that keeps on giving.