“Say to the believing men that they should lower their gaze and guard their private parts; that will make for greater purity for them. Indeed Allah is well acquainted with all that they do.” [An-Noor 24:30]
“So Allah made purification and spiritual growth to be the outcome of lowering the gaze and guarding the private parts.”
Ibn AlQayyim AlJawzee
Lowering your gaze (for the sake of Allah) = Purification and increasing your chastity. The pleasure of lowering the gaze is not like the small pleasure of staring.