All that spin-offs

I'm watching anime since I was a kid. I've watched a lot of anime, and my favorites are Pokemon, Digimon, Yu-Gi-Oh, Dragon Ball, etc. And I realized one thing that happens all the time. I'm delighted wit the original run of the series, but when it comes to the spin-off or the sequel, I don't like it that much. I'll take Yu-Gi-Oh for example, I absolutely loved original run with Yugi and Kaiba (I also liked GX), but When it came to the 5D, I almost stopped to like it at all. The same thing happened to almost every anime I've watched. And I noticed, that I don't like the sequels. I don't know why, they just aren't interesting to me. So I'd like to ask you, I'm I the only one who doesn't like the sequels, and what do you love more original series or the sequel?

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