From UX point of view, what is the rationale behind using location of device to select web-site language instead of device's language settings?

Question

My question is exactly what is says in the title.

I've noticed this behavior being common in web-sites and mobile phone applications getting content from the Internet and I do not understand why it is so common. For example, Google Play Store will often use device's language setting for application itself and display all data it gets from the Internet in local language.

Both modern browsers and mobile telephones have language settings. When a browser connects to a web server and requests a page, it will also send a list of acceptable languages together with the request. That list will (by default) at least have on it the language used currently by the browser and users themselves may edit them. Mobile phone applications already know the device's language settings and should be able to send them when connecting to their server. I wouldn't consider it unreasonable to assume that user uses understandable language settings in browser and for the phone's OS.

What I've seen instead is that websites and applications use geolocation to determine the language which they will use when displaying page. While, at the first look, this may not seem a bad idea at the first look, geolocation,especially if combined with inconsiderate* web-site design, will make things very difficult for people who are traveling or who are cursed to have their location incorrectly detected.

So what improvement does geolocation give over just using language settings that device already provides?

P.S. Sorry for the bad title, but I couldn't figure out anything better!
*By inconsiderate I mean gems such as having a language selection menu where names of languages themselves are translated or even incorrect.

Answer 1

Theres some scenarios I can think of. While I agree I would especially prefer for them to use the devices language settings here or some scenarios I can think of to possibly use the Geo Location.

1. Areas Where users know multiple languages and the translation doesnt really make as much sense. Users In the english speaking Toronto visiting the french Speaking Montreal. If a map app said stop instead of Arete a user may be looking for a stop sign rather than the french word of stop (Arete) and may not be as sharp in the driving context. Or possibly trying to translate street names when there is no need to do so.
2. If your using a top notch translation service and you only support a few languages and thus anyone not in those markets you default to your "other language". Ie if your describing interior design services and you paid for expert translation for german english and russian rather than throwing in a half baked algorithm attempted Chinese translation that people would know is of low quality you default to whatever one you think people will most likely know (maybe english) rather than users with their device settings in Chinese to think that your site was rushed or perceived to be of low quality. I know when I read sites or menus with terrible grammar and miss spelt words I think the quality will be less.

Those are just fringe cases on why you might do it. In general its a [bad idea], and your geolocation isn't always that accurate 1