Considering cortana is capable of being trained to your specific accent can't really say it's shit without extensive use... Plus there have been dictation pro software for more than a decade that work really well, pros wouldn't use it otherwise... Dragon software from nuance is great and very efficient example that proves that voice recognition is achievable with excellent results
And cortana is far from being just a voice recognition software, I use it everyday on my PC and smartphone with the keyboard to manage my calendar di my searches and other stuff








