For native speakers, variants can be unintelligible or be unacceptable in educated contexts. English speakers may understand a handwritten note saying "4P5 kg" as "495 kg", but writing the nine backwards (so it looks like a "P") can be jarring and would be considered incorrect in any school. Likewise, to users of one CJK language reading a document with "foreign" glyphs: variants of can appear as mirror images, can be missing a stroke/have an extraneous stroke, and may be unreadable or be confused with depending on which variant of (e.g. ) is used.