In Star Trek: Voyager, the ship and crew spent over seven years in the Delta Quadrant trying to find their way back home. During that time, they encountered aliens, had battle after battle, and went through some dark times. Voyager was consistently damaged during some of those battles, but it didn't stay that way. And that was a bone of contention with writer Ronald D. Moore, who, according to a report from Brannon Braga in The Fifty Year Mission The Next Twenty-Five Years by Mark A. Altman and Edward Gross, wanted the ship to show evidence of its wars.
Braga said Moore wanted the "characters to have lasting consequences" and also wanted to "eradicate the reset button." Unfortunately, the studio wasn't interested in that because of the potential for syndication. Braga admitted that he "made a big mistake by not supporting Ron in that decision." And it certainly would have made a lot more sense for Voyager to have born evidence of its extended battles.
This was a crew trapped out in the middle of nowhere with no access to assistance from Starfleet and no way to rebuild the ship. There certainly wasn't a repair station nearby. So how did Voyager stay in such good shape? That was never explained, and, at the time, it was like continuity didn't matter.
It would have been more realistic to have had a scarred and damaged Voyager limp its way back home on its last leg after struggling for so many years to survive in a desolate part of the galaxy. Instead, it glided toward Earth in its final episode without so much as a scratch. A bit unrealistic. At the very least, there should have been some explanations as to why the ship was able to be repaired so easily without access to a repair station.