How come in TV series the scenes in "previously on " section differ from the same ones from the last episode?

Question

In almost all TV series (drama, action, comedy, even cartoons) that have episodes following on from the previous one, there is a "previously on [tv series name]" section, and in this section they have short cut outs from previous episodes' scenes relevant to the new episode. However most of the time these scenes will have subtle differences to the actual scenes shown on the previous episode; for example the dialogue will differ by a few words. Why is this?? Why do they not copy and paste the scenes from the past episode and instead have a retake??

Answer 1

usually a combination of a number of prior episodes not just the one from last week. and they have alot of editing and stuff they did not get to show

Answer 2

The reason for this is that they are trying to give the viewers a reminder of what happened in the last episode, without going into detail. Meaning that you do not have to see or hear every scene from the last episode, just the important lines or happenings.
This way, when you watch the episode, they have already gave you a refresher on the last episode and you are ready to continue watching the series.

Answer 3

They're just trying to give a quick update on what's happened in the past episodes to keep the story line fresh in your mind.

Answer 4

The only show I watch that does this is ER. Their "previously on ER" clips are always the same scenes as I watched when they aired.

Answer 5

I've never noticed any dialogue changing in those...they cut out words here and there to condense it, but I don't remember them using different takes or anything...

Answer 6

its so they can change the storyline without having to reshoot the whole previous episode...making someone look guilty when they're not and drawing you in.

Answer 7

Because he never got out of the cockadoodee car!!