I don't see what was bad about it. It sounds like it does on record. She always does the breathy style singing in the higher parts of the song. The only thing that she added was the baby style talk every now and again. But I still say this was a good performance for what she is supposed to be. A flashback 60's/70's singer-songwriter. I love her huskiness in her voice, that's so different from the light airy voices you hear on the radio. I agree with the consensus that the performance was rushed and she may have been a little nervous though. The song itself is 5 minutes and more, yet they gave her barely 3 minutes to perform it.
She needs to get over her stage fright if she wants to smash. Some artists can get hits without ever performing well, but I don't know if that works with her genre of music...
After seeing the reaction here I was expecting it to be worse than it is. Or maybe the reason I think that is because I was prepared and just took it for what it was. She looks nervous and I don't really like how she sings it live in some parts but it wasn't horrible.
She sounds weird, with some odd accent. Especially in the first reprise when she sings 'I tell you all the time, heaven is a place on earth with (wiv?) you'. (1:05)