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Localization is the feeling that the website was originally created for that country.
According to Shopify, displaying prices in local currency can increase conversion by up to 13%. Users are a third more likely to complete a purchase if they see a familiar currency.
Source: https://www.shopify.com/enterprise/blog/multi-currency
The result is clones, fragmented URLs, competing versions, and cannibalization. According to Ahrefs, up to 60% of multilingual sites have errors in hreflang or structure, which directly affects ranking.
Source: https://ahrefs.com/blog/hreflang-tags/