Read the following selection from Act II of Romeo and Juliet. What does the line in bold most likely mean?

JULIET
The clock struck nine when I did send the nurse;
In half an hour she promised to return.
Perchance she cannot meet him: that's not so.
O, she is lame! love's heralds should be thoughts,
Which ten times faster glide than the sun's beams,
Driving back shadows over louring hills:
Therefore do nimble-pinion'd doves draw love,
And therefore hath the wind-swift Cupid wings.
Now is the sun upon the highmost hill
Of this day's journey, and from nine till twelve
Is three long hours, yet she is not come.
Had she affections and warm youthful blood,
She would be as swift in motion as a ball;
My words would bandy her to my sweet love,
And his to me:
But old folks, many feign as they were dead;
Unwieldy, slow, heavy and pale as lea

From nine a.m. to noon is three hours, but the Nurse has not returned.
Juliet has done three hours' worth of work, but she is still not tired.
The Nurse has not sent word back to Juliet in nearly three full days.
Romeo lied when he told Juliet that he would be ready at nine a.m.