Wow! I was starting over. Thanks for creating this video.
...Deb
Using Punch in not only eliminates the need to start over from beginning, but you can also create a comp recording. For instance, use this feature to record a vocal line by line or play a difficult lead guitar part. I personally prefer to record the entire song and then go back and correct mistakes but there are artists that meticulously record line by line, perfecting as they go. It's a preference that's available in BIAB if someone prefers or wants to experiment with the method.
Not mentioned in the video but you can also overdub recorded audio allowing you to create harmonies, vocal doubles, add your own ooh's and aah's and you can also punch in over existing recorded audio.