Boss battles are those infamously devious parts of video games, when one's progress is put to the question of his/her's ability to surmount this newly-presented obstacle. Many a time you will stumble upon such "immovable objects", often when least expected, and you'll need to simply convince the game that you're the "unstoppable force", and strike just as hard back.
But, surprisingly, boss battles are often the defining moments that bring you closer with the game, rather than push you away. There are times when video games are considered as good as their weakest boss battle. And there are times when a boss is so well designed, thematically and virtually, that it is the first thing you'll think about when you think of that game, henceforth.
Certainly, there are boss battles who I'd love to experience freshly again, just to sense the excitement of slowly understanding how to defeat them again, for the first time. Does that makes sense? Well, assuming that medicine will one day very likely come up with a procedure that will be able to remove specific memories of our RAM (so to speak), it can make a lot of sense, indeed. Of course, it's all just wishful thinking now... But, here's to hoping!
(SPOILERS IF YOU HAVEN'T PLAYED THESE GAMES, DUH!!!)