A restoration I imagine most people will think of this as the best-case example of the idea:

For ‘Seven’ Restoration, David Fincher Went Back and ‘Kissed in Some of the City’

“It is what it is, warts and all,” Fincher said. “And some of it is spectacular and some of it is stuff that I would change or fix today, but I didn’t want to mess with that. There’s a lot of imperfections, there’s a lot of things that you just don’t see on film. When people say they love the look of film, what they’re talking about is chaos, entropy, and softness. Now, of course, we live in an HDR world where you get those kinds of very deep, rich, velvety blacks for free.

“And we had to negotiate that fine line between what to fix or not,” Fincher continued. “So we attempted to go back in and fix to make it match. And kind of repaint stuff and just take out water spots and little edge flashes. And some of it is impossible to get it to match, certainly by today’s standards. So there was a lot of excavation. I didn’t realize it would take as long as it did, at least six months dealing with files and making notes, and maybe the last nine months to a year putting some of it on the back burner while we finished ‘The Killer’ and did initial work on ‘Panic Room,’ which is what we’re working on now.”