要点In short
- A machine-translated /ja section passes a grammar check and fails the trust check — clicks happen, conversions don't.
- The failure isn't linguistic. The information architecture is still built for a Western reader's decision process.
- Around 90% of Japanese consumers will only read content in Japanese, and unnatural Japanese actively destroys trust rather than merely underperforming.
- Localization is a foundation task that belongs before advertising, not alongside it.
It looks efficient: add a machine-translated /ja section to your existing site, then start ads and PR the same week. It's also the single most common way foreign companies waste their Japan budget.
Why it fails
- Grammatically correct but unnatural Japanese collapses Trust Layer 04 — copy quality signals whether you're serious about the market.
- The information architecture is still built for Western readers, not the Japanese decision process.
- Trust signals — address, phone, corporate number — are missing, so Trust Layer 01 (existence) fails on arrival.
- You pour ad spend into a page that visitors bounce from. The budget is real; the results are an illusion.
It's like pouring water into a bucket full of holes. The cost is real. The result is a mirage.
What localization actually means
Localization rebuilds the page for how Japanese buyers read and decide: native copywriting, restructured information, and the trust signals a Japanese visitor looks for first. It's a foundation task, not a translation task — and it has to come before advertising, not alongside it.
The order is the whole point. Marketing before the foundation exists produces nothing. Build the Japanese web presence first; then the same ad spend starts converting instead of evaporating.
Sources
- 01CSA Research, “Can't Read, Won't Buy” (29 countries, 8,709 respondents)
- 02EF English Proficiency Index 2025 — Japan
Takato Minemura — Founder, JIN MARKETING
Takato Minemura is the founder of JIN MARKETING and runs WINDE, a development company in Japan. Educated at university in the United States, he spent years working alongside businesses abroad, where the same request kept arriving from the founders he worked with — we want to bring this to Japan, how does it actually work there? Answering that question repeatedly showed him something he had not expected: what he had treated as ordinary common sense about marketing was in fact specific to this market, and the companies committing the most money to an entry were the ones least aware of it. He works on both sides of an entry, the strategy and the code that implements it, which is why the research here comes out of projects rather than desk study. More about the author