Desires, material and spiritual
Krishna fulfills everyone's desires, but He gives His devotees special treatment.
For example, if we want to become Krishna's devotees, but at the same time have material desires, He may fulfill our "not so spiritual" or mixed desires in a way we might not like—just to help us become free from that desire.
Or, if one is very sincere, He may overlook a "not so pure" desire and satisfy it in a roundabout way. If our desire is purely to serve Him, He will satisfy it to encourage and promote our service. But if it's tinged with false ego, he may nip it.
In other words, He will do what is necessary for the sincere devotees' advancement, knowing that the servant will accept His arrangement. He will try His best to correct and purify whatever inclinations we have that will hamper our devotional service.
Krishna also fulfills the desire of the nondevotee, even though it might not be for his spiritual good. He has granted us all a tiny bit of independence, and He honors our right to desire anything and everything.