Although you know me well,
You never gave me a name.
I greet you cheerfully every single day,
Yet your dull reply is always the same.
You may hate or love me,
But you only ever whine,
For often when you need me,
I am not there in time.
I do more for you than you could imagine,
Every single day, I am there.
And yet for all of this, in the end,
You leave me without a care.
Who am I?