The 'Heaven' hitmaker - who has penned tracks for a diverse range of artists including Susan Boyle and Tinie Tempah - admits she can't sleep if she is disappointed with her work.
She said: ''I never commit to one tribe of music.
''I love to write for Susan and I love to write for Tinie Tempah - it's all good. The only criteria for me is; is it a good song or not?
''One thing that will keep me awake at night or make me disappointed in myself is if I am lazy with a lyric or if a melody doesn't hook anyone.
''So I don't mind who I work with or what it's for as long as the song is actually good.''
Emeli insists she has never set out to be famous and just wants her work to leave a lasting impression.
She added to Britain's Elle magazine: ''I've noticed from meeting people my age in the industry that they come in with this ambition to be really famous.
''But honestly, my ambition from the very beginning was to be a great writer and to be remembered as one.
''I wasn't chasing any trend. I wanted to write lyrics that whenever I sing them - or someone else is singing them - mean something and touch people. I want to make music that will last.''