Alright, let's just throw out the 'physics'. Well, let's just set it aside for now... Like a slice of pie.... (hmmm... pie

)
The Sorceress is the equvilent of "The Anti-Christ" or "Demi-God" and the power has only evolved and strengthened with each generation. Now what could be the ultimate goal of the Ultimate Sorceress with the Ultimate Power?
You take all the time of the peak of that power's evolution and absorb it into yourself and snatch one moment in time and make it everlasting. Forever... Eternal. Say, your greatest moment in your life, your greatest and ultimate victory and that day NEVER NEVER ends.... That is what Time compression is: The everlasting moment...
1= Past
2= Present
3= Future
1.5= Actual present
1+2=3
3/2=1.5
In effect, Ultimecia is now safe from the never ending witch hunts because she remains in an everlasting moment of time and everyone else has moved on...
Get it? Listen to "Eyes On Me" and Ultimecia's last words. Then, if you can, watch the final scenes and maybe it'll clear things up.
