Everyone has been through this: You get super excited for something and get disappointed. That particular thing could still have been great but just didn't meet the extremely high expectations set. And in many cases it's not even your fault; sometimes your friends/media/companies build up so much hype that it's impossible for anything to meet the expectations. This may be one aspect of the Leeroy Theory.
For example for the past month or so, Samsung slowly built up anticipation for the sucessor to their very popular Galaxy S3 with teasers for the Galaxy S4. While most of the features and specifications leaks the past week, many techies were still very enthusiastic about unannounced features. The announcement event seemed to have an Apple feel to it, that it was going to be watched by not just people within the industry but average users. But it was at 7 pm Eastern Standard Time which was odd and it had an odd Broadway style delivery to it; I wasn't very fond on it. But the only feature not leaked prior to the event was the ability to use the phone with gloves on (probably with Synaptics technology, already used in Nokia devices). So overall, I was disappointed since nothing really innovational was introduced to the phone (well, nothing that an average user would find useful). And once again, I am disappointed that the speaker is still on the back; why can't device makers see that speakers on the back of phones make absolutely no sense?
So how can you avoid the downfall of hype? The best thing is to not listen to your friends or read/watch anything. Or if that's not possible, you can try to set your expectations really low; sometimes this is not possible like waiting for Arrested Development, it's been years of built up excitement (Tobia once said: I’m afraid I prematurely shot my wad on what was supposed to be a dry run if you will, so I’m afraid I have something of a mess on my hands.) As with anything, it's all about self control. Sometimes waiting it out is the best thing to do like I have for "Midnight in Paris", "The Hobbit", "The Dark Knight Rises", and so many other things. Movie hype may be the most common but it is easy for me to forget it. Or I go into the movie pretending Jason Bateman is in the movie; that lowers the expectations enough every time. Food hype most be the most disappointing type of hype for me; people commonly overstate the quality of the food.
But the best feeling has to be when the hype is high and your expectations are met. Hasn't happened to me very often though.