To answer your question, there are 2 scenarios for me where this feature comes in handy.
1. Lets say you have an instrument connected and trying out new ideas on guitar or vocals. But you are actually not recording your improvisation yet, just warming up. Then if you realize you just played something great, you can simply press record, stop the recording and then be able to extend the recorded region up to 1 minute extra before the point in time when I actually pressed record. In that way you can save a good idea that otherwise might have been lost.
2. You record an artist, only to realize you might have accidentally pressed play instead of record. If then you realize this before more then 1 min has elapsed since the vocalist started singing you can simply press record during playback and the everything the minute up to before you press record will be saved. Very handy indeed!
If Presonus would give the Studio One users the option to extend the pre-record to more than 1 minute, more ideas and performances could be saved this way.