What's with sequel's having to be "ALL NEW"?

Is the definition of sequel unclear

Posted on Wednesday, October 29, 2014

I've seen a lot of people on here complaining about this both with GalCiv3 and Civ:BE and I don't get it.  These games are sequels not spin-offs.  You buy a sequel because you like the original and want more of it.  There's been 6 Star Wars movies and 12 Star Trek movies, both with more coming.  If the new Star Wars movie comes out and is a musical, you're going to be like WTF?  It's a sequel, it's supposed to pick up where the previous left off.  GalCiv3 and CivBE both do this.

That's not to say you can't have complaints about the games, but people are upset because "hey this is just like the last one".  Yeah, duh, it's a sequel.  I would pay good money for Warlords Battlecry III or Battle Chess to be remade exactly as it was except with updated graphics, widescreen compatibility, and Win7/8 support. Sometimes that's all you want.  If they add more than that, great.  But don't re-invent the wheel.  If I buy Warlords Battlecry IV and get a shinier Warcraft III, I would be severely disappointed.  

I'll admit there's an argument to be made about Expansion/DLC vs Sequel with CivBE given how much is recycled but I still don't see why you would expect it to be anything other than CivV in space?