If you want to update the site title of a SharePoint site you probably will use the title property of your web object. ok, but this will only update the site title in the language of the user that runs the code.
e.g. my user account has set English as default display language
If you update web.title property trough the UI or via custom code, change your default display language to another language and load the site again, the web.title property won't be changed in this language.
You can use this piece of code to change the title property for all available languages of a site.