I found a great article today about how we can think about the various ways in which parts of games interact. It talks about the relationships between input, problems and feedback and the impacts of having too much of one thing or another on your game. In particular the author talks about the issue of having too much feedback and not enough problem in your game; you end up with very little replayability. He gives examples of games in which you have a trivial situation with only one solution but which is also filled with great cinematics. An example of this is the final action you take in Portal 2 where you must simply aim your mouse at the moon and click. It is followed by a long and enjoyable cinematic but that particular push and click is really nothing at all; certainly it isn't much of a challenge. Fortunately for Portal 2 the immediately preceding portion of the game is all about mad clicking and problem solving so it doesn't get in the way. However, if the whole game was just a few simple clicks with no skill or thought required followed by fancy graphics it would be a pretty terrible game. You might enjoy it the first time but clearly it should be a movie, not a game.
This sort of situation is becoming more prevalent in the world of MMOs. Most early MMOs were brutal and punished failure severely; they were certainly not a place where anybody who can click a mouse would just cruise through watching the pretty screen. I would say they were too brutal, in fact, but you would not accuse EQ of having too much cinematic and not enough doing stuff. Modern MMOs have swung pretty far the other way. SWTOR marketed heavily their voice acting and cinematics and from all accounts those things actually went over very well. They have a long story with lots of things to watch and experience but you know what is going to happen the second time through; players will hit Esc and get out of the cinematic to get to the next quest. It is the same thing as the "you beat the Lich King!" cinematic in WOW. The first time we downed him we all watched it all the way through and it was a fantastic moment but the second time he died we went straight to looting.
Cinematics and other narrative elements are great to have in a game but they aren't enough long term. If people want a great movie experience they generally don't sit and watch the Godfather series over and over; they go on to other movies and other stories. The same holds true in MMOs and other games. If you want to hold people's attention long term you can't focus entirely on feedback and ignore the problems and input portions of the game. For players to continue playing and to keep coming back you have to either have fresh new feedback (and that is quite clearly impossible as nobody can make enough cinematics and content as fast as players can consume it) or have interesting problems and input challenges. Maybe your game is obvious strategically but difficult to execute like a car racing game or maybe it is a game where figuring out what to do in the first place is hard but actually doing it is easy like HOMM. In either case you have much more chance of keeping the interest of the player than if you simply try to have your game be a movie with a few easy clicks in the middle.