7 bilingual website translation mistakes that make visitors leave

Many Vietnamese businesses invest in an English version of their website, then watch international visitors bounce within seconds. The culprit is usually not the design or the load time. It is the language quality of the translation itself.

Why do foreign visitors leave even when the site has an English version?

Because a bad translation does more damage than no translation. International visitors read your English pages with a native speaker's eye: one odd sentence in a headline, one button still in Vietnamese, one price they cannot convert is enough for them to conclude the business is not ready to serve them. Trust is lost before they ever reach the part you are best at.

The data shows language directly shapes purchase decisions. The Can't Read, Won't Buy - B2C survey, run by CSA Research with Kantar in 2020 across 8,709 consumers in 29 countries, found that 76% prefer to buy products with information in their native language, 65% prefer content in their own language even when the translation quality is imperfect, and 40% will never buy from websites offered only in another language. In other words, customers are forgiving about the fact that you translated, but unforgiving about sloppy translation at the touchpoints that matter.

Chart: the three headline figures from CSA Research's Can't Read, Won't Buy - B2C survey (2020). The scale is the percentage of respondents agreeing.

This article focuses on the language quality of the translation. If you need the technical side, hreflang declarations, x-default and multilingual URL structure, see the earlier article on website localisation and hreflang. The two complement each other: the technical layer brings the right person to the right page, and the language keeps them there.

The 7 translation mistakes that make an English version backfire

1. Word-by-word translation that clings to the Vietnamese

The most common mistake and the easiest to spot. The slogan "Đồng hành cùng doanh nghiệp Việt vươn ra biển lớn" translated word by word becomes "Accompany Vietnamese enterprises to reach the big sea", which native readers understand and quietly laugh at. Vietnamese loves metaphor and long sentences; commercial English loves strong verbs and short ones. The fix: translate the idea, not the words. Rewrite the sentence the way a native speaker would express that message, then check it against the original to make sure nothing was lost.

2. Untranslated meta tags, alt text and buttons

The body copy is carefully translated, but the title tag, meta description, image alt text, the "Gửi yêu cầu" button, form error messages and the confirmation email stay in Vietnamese. The damage is double: search engines show a Vietnamese headline to people searching in English, so few click, and visitors who do arrive get stuck exactly at the conversion step because they cannot read the buttons. Microcopy is small, but it sits at the deciding touchpoints. The fix: list every text string outside the body copy, including the 404 page, breadcrumbs and the cart, and translate 100% of that list.

3. Two languages mixed on the same page

An English page where the menu still says "Dịch vụ", the footer says "Liên hệ" and a promotion popup fires in Vietnamese. For the visitor it is a maze: they do not know what to click and will not risk filling in a form. For machines the language signal is noisy: the lang attribute declares one thing while the content says another, making it hard to file the page under the right language. The fix: one page, one language, and check the shared parts, the header, footer and chat widget, which are the pieces most often missed because they live outside the content files.

4. Machine translation published without editing

Also from CSA Research: 66% of consumers resort to machine translation tools themselves when a website does not offer their language. That means machine translation is not the enemy; it is a fast, decent first draft. The problem is publishing that draft with nobody reading it: wrong nuance in pricing, terms and warranty commitments, where one skewed word can become a real dispute. The fix: let the machine build the frame, then have someone fluent in the target language edit, starting with the sales, pricing and legal pages. The full workflow is in the website localisation article.

5. Terminology that changes from page to page

The homepage calls the service a "phygital showroom", the pricing page says "hybrid store", the blog writes "physical-digital space". Three names for one thing make customers think you sell three things, and make it hard for search engines and AI systems that summarise the web to gather signals about a single service. The fix: lock a terminology table before translating, marking which words stay untranslated and which get one fixed rendering. That table belongs in the same kit as your brand guidelines for SMEs, so the content team and the translation team share one source.

6. Forgetting date, currency and number formats

The string 07/08/2026 is 7 August to a Vietnamese reader but 8 July to an American one; a price of "5.000.000 đ" leaves a foreign visitor unsure whether it is expensive or cheap. On a promotion page with a deadline, that gap is enough to lose an order or trigger a complaint. The fix: on the English version, spell dates out as "7 August 2026", show prices with a reference conversion, for example "5,000,000 VND (around 190 USD)", and state the time zone for every event.

7. A tone that is wrong for the target culture

The hardest mistake to see, because the sentences are grammatically correct. Self-introductions like "number 1 in Vietnam, proudly honoured" feel familiar at home but raise doubts with Western readers used to concrete evidence; the multi-layered formal address of Vietnamese carried straight into English sounds heavy, while commercial English favours the direct and brief. The fix: define a voice per language instead of translating the voice, in the spirit of the article on tone of voice by situation, and replace self-praise with numbers, certifications and delivered projects.

An afternoon-long process to audit your translation

You do not need strong English to catch most of the 7 mistakes above, because most of them are process errors rather than language errors. Sweep in this order:

Finally, remember the touchpoints after the website: if you run a virtual assistant that answers customers, it must reply in the language the customer is using, with the same terminology, the mirror image of the approach in the article on training an AI agent to speak natural Vietnamese. A polished English website whose chat replies in Vietnamese still breaks the experience.

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