Done Wrong??

The clouds always come in
Promising rain on a barren land
But instead,
Cause a storm hitherto unseen.
She looked up at the sky,
The sun blazing down on her,
Wondering when would
The skies open up....
And drench her to the core
And may be hide her tears!!
She stared into the unseen
A heart full of Desires...
Yet to be realised
And a hope that refuses to die.
They say,
"Wish with a true heart,
And your dreams will come true".
Isn't that's what she had been doing?
Then why doesn't it rain?
What has she done wrong??