I wouldn't say they "failed". QR-codes are one of the things which are now everywhere and weren't there a few years ago at all (see barcodes weren't use in all

I wouldn't say they "failed". QR-codes are one of the things which are now everywhere and weren't there a few years ago at all (see barcodes weren't use in all the places where now a QR-code stands). The fact that not many people cares to scan them (citation needed) is a different thing... still they are quite popular.