A predictable plot isn’t inherently a bad thing. People that make you think that a predictable route in a story is in fact a bad thing and makes the story lesser are wrong. Yes, I went there with the statement. I do not believe that a predictable plot or ending is necessarily a bad thing. That doesn’t mean that it isn’t a bad thing either. To be a bit more specific, you need to take a look at the story as a whole and understand if it is the preditable plot bringing the story down or something else.
A predictable plot means that the story is moving through expected beats. You see what is going to come next and aren’t given any major twists and turns. Sure, the detals may be unique, but you know the general direction of the story before it comes. That is a predictable plot and it isn’t necessarily wrong. For one, a predictable plot goes through the beats. The problem with predictable plots occurs when a predictable plot is paired with uninteresting characters. A thrilling character that makes you want to spend time with them can make a plot you see coming from a mile away feel worth it. Just like a predictable plot can be jazzed up by playing on expectations and while not changing what happens, changes the exact way the characters get there. That said, a predictable plot is going to be more difficult to pull off than a a story that doesn’t telegraph all of it’s moves.
A predictable ending, doesn’t necessarily come with a predictable plot, however there is enough to make it clear what is going to happen. A predictable ending is often telegraphed in so that you know what is going to come. Often you can’t tell how the the journey will get you there, but you can see how it will end. This is often found in long running tv shows. You spend so much time with characters that you get to a point here there is no other ending that you can imagine. Thus a predictable ending can be tacked on to a story that otherwise threw you on loops throughout. One of the things that comes with a predictability is satisfaction. You were able to figure out how it turned out, leading to some sort of feeling of intelligence.