Dream sheets...aka Base of Preference (BoP) filled one out at Basic with no idea what each base did. My choices were all overseas...got sent to Dover AFB.
The only time we qualified for a BoP during my time is if one was coming out of a special duty assignment or a remote overseas. In other words, you earned it.
Though there were problems with that in the past.
I knew folks that would be sent overseas for a year and come back to the same base, squadron and most times, flight that they left, numerous times. A revolving door that prevented them from going other places. A real morale killer, especially for F16 maintainers rotating to "The Koon" (Kunsan) and back.