Translation is replacing words.
Localization is the feeling that the site was originally created for this 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 their familiar currency.
Source: https://www.shopify.com/enterprise/blog/multi-currency
This results in clones, fragmented URLs, competing versions, and cannibalization. According to Ahrefs, up to 60% of multilingual websites have errors in hreflang or structure, which directly affects ranking.
Source: https://ahrefs.com/blog/hreflang-tags/