As a psychologist, I often like to apply my trade to perceptions of videogames, to understand why gamers react the way they do to certain things. I'm going to talk about a few principles of social psychology, and how they might apply to gaming.
1. Expectations influence perceptions. This one is pretty simple. People tend to see what they expect. To give an example of an actual study, people were told they would either be watching a video of "soccer fans" or "soccer hooligans" at a soccer game. Both groups were shown the same footage of people celebrating at an international soccer game, and asked to rate several aspects of their behavior. Not surprisingly, the group expecting to see "soccer hooligans" rated the behavior as much more aggressive.
So what about videogamers? The buildup to a game release is a big factor. Take Joe Halo, who loves, well, you know. He knows Halo 4 is gonna be coming out soon, and he just knows it's going to be fabulous. so he expects the game to be great. So naturally when it's released, he thinks it's the best game ever.
Why does this happen? For one, we have a tendency to seek information that confirms our expectancies. This is called confirmation bias. We notice things that confirm our expectations, and ignore or undervalue things that don't. Thus, we really pay attention to when something good or exciting is happening (e.g., a plot twist, a tough boss) but don't when something bad or annoying is happening (e.g., long, boring hallways, mindless, easy combat).
Second, our expectations drive our perceptions of ambiguous events or behavior. For example, a shoulder bump as you walk past someone can be hostile or accidental. Which is it? If you expect the person who bumped you to be aggressive, you're going to interpret the bump as hostile. Likewise, if you expect a game to be incredible, you're going to interpret ambiguous things (e.g., the average puzzle) as being great.
You might find yourself thinking, "Well, if a gamer builds his expectations too much, they will be unrealistically high, and he's setting himself up for disappointment, and would actually make him see the game falling short on expectations, and thus bad."
No, not really, which brings me to point two.
2. Cognitive dissonance. Cognitive dissonance is a fancy bit of jargon for "When you feel one thing and do another, it makes you feel bad." So if you think you need to lose weight and you eat two bacon double cheeseburgers, chili fries, and a 64 oz. coke for lunch, you'll feel bad. Likewise, if you spend 4 months convincing yourself a game is awesome, claiming it will be awesome on message boards, and telling your mom how awesome it will be, you're going to feel like an idiot when it sucks.
When it comes to removing dissonance, you can do one of three things. Change your attitude, change your behavior, or rationalize. Without going to deeply into this, the easiest thing to do is change your attitude. So if you can maintain that this average game is really great, you maintain a consistency between attitude and behavior, and you feel fine.
This also applies in making decisions. If you have a choice between two consoles, for instance, you're going to play up the positives and downplay the negatives of the one you pick, and do the reverse for the one you didn't pick. What this does is make you feel more consistent in your actions.
I'm out of time now, but I haven't really gotten to explain as much as I wanted to. But I think this will work as is. On a final note, all of this stuff happens without our awareness or intent, so it's not like you can turn this on and off at will, or realize that it happens. But at least you now know that it happens, which is the first step to being a more discriminating gamer.