By play the same stuff I mean play the same part of a level repeatedly. This problem occurs more with console games than computer games because console games have less flexibility in game saving.
Example: Metroid Prime
I'm going to use the game Metroid Prime to describe the problem of playing the same part of a level repeatedly for two reasons. One, it's the game I'm currently playing so it is fresh in my mind. Two, it's a really good game. I want to show that even good games can have minor problems.
If you're wondering why I'm playing a 4 year old game, I'll explain it now. I got Metroid Prime about 3 years ago and I got stuck early and quit playing it. I started playing it recently because my brother needed my Playstation 2 to play DVDs because his DVD player broke and I finished my other GameCube games.
Repetition Can Turn Something Fun Into a Chore
Metroid Prime features a lot of boss enemies to fight, and they can be very difficult to defeat. To reach a boss involves fighting lesser enemies, running, jumping, maneuvering the morph ball through tight areas, and problem solving. Sometimes it can take 5-10 minutes of gameplay to reach the boss, and when you die, you have to go back to the last save point and play those 5-10 minutes again.
Because some of the boss enemies are tough to defeat, you can die dozens of times, and replaying the same 5-10 minutes of gameplay to reach the boss gets old fast. Playing those 5-10 minutes to reach the boss is fun the first time. You're making progress in the game and exploring new areas. Playing to reach the boss a few more times lets you perfect your technique. But after dying 25-50 times, playing the same sequence to reach the boss becomes a chore instead of being fun.
One solution to the problem of having to play the same area of a level repeatedly is to provide more save points. In the case of Metroid Prime, having a save point before reaching a boss would prevent the player from having to play the same sequence over and over again. But more save points could make the game too easy. Metroid Prime replenishes your energy (health) to 100% when you save the game.
Another solution would be to continue the game where you died. In the case of Metroid Prime, being able to fight the boss right away after dying would eliminate a lot of frustration. The time spent getting to the boss could be spent on the real challenge, defeating the boss.
The good news for most of the game developers reading this is you're developing computer games, not console games. Computer games can let the player save the game whenever they want so you can keep the player from playing the same sequence over and over again.