Tahajjud is the truest love for Allah, after all, doesn’t every lover desire to enjoy the privacy with his Beloved?
“And those who seek forgiveness before dawn.” (Ali-Imran:17)
The middle of the night is reserved for the lovers who wish to spend time in seclusion with their Beloved (Allah) and the end of the night is reserved for the sinners to seek forgiveness for their sins.
Whoever is unable to join the striving of the lovers in the depth of the night should at least join the sinners pleading forgiveness at the end of the night.
‘I cannot imagine that someone would sleep during the last part of the night!’ (Tāwūs)