UT McGovern's phiosophy is that they want the students to be in love with them. How they determine that, only they know.
As far as I could make out their process - they give prematches to people who they think mostly will rank them 1.
Rest they rank in the order of preference and see if they truly want to come to UT Houston during the match. This is because many they might like also get prematches elsewhere and those with prematches have to deliberately select UTH #1 to match there assuming UTH also ranked them high enough.
OTOH,
@wysdoc's advice above works well to keep your sanity.
🙂