Honestly for me it's mood dependent. Feel good during the day -> enjoy staying up literally pacing till 2AM. Feel like an unmotivated lump that can't do anything -> sweet, sweet oblivion.

I guess that's related to what another commenter said, that essentially we stay up because it's more fun than the alternative. One thing that works for me as a result is focusing on dreams or stories I tell myself at bedtime to generate fun dreams. Another thing is give myself a goal where bedtime is somehow the reward (I will fold all the laundry and bake cookies, but then I have earned going to sleep) and it will make me feel like going to sleep is desirable even if in actuality laundry and cookies sounded much better.