Teams often postpone Arabic until the product is ‘finished’. That usually turns localization into a costly retrofit because directionality, content length, typography and mixed-language interfaces have already been baked into the design.
RTL is an architectural concern
A reliable bilingual system needs route pairing, semantic language metadata, mirrored layout logic, component-level direction testing and deliberate handling of mixed LTR strings such as product names, URLs, numbers and code.
Search engines also need explicit pairing
English and Arabic pages should have stable canonical URLs and reciprocal language alternates. Translation quality matters, but so does the technical relationship between those pages. A user and a crawler should both be able to move between true equivalents.
Operational parity matters more than literal parity
Good Arabic localization preserves intent, hierarchy and action rather than forcing every English phrase into the same physical shape. The best bilingual products feel native in both directions while sharing one underlying product system.