Without knowing a lot more, it might be hard to say why this game turned out how it did, but there is something I think is important:

We have one for the studio. Our motto is "Great games are played, not made," meaning you can spend a lot of time on paper coming up with great ideas, then as soon as you put it in the game, you're like, "I was thinking wrong." So we try to just bullet point things on paper, then get it in the game, play the game, and get ready to throw your ideas out.

With Skyrim, the dragon's design was a one-pager. "Those are gonna work." A couple bullet points was what we were going for. One of our other rules is "define the experience." With dragons, it was more about defining the experience we wanted to have as opposed to "here is the feature set and technical design, etc. etc."

When it comes to game features, we are more about iteration. The only area we're document-heavy in is the content of the world. We have to be, with all the people, quests, items. We're very document-heavy and we have a really slick wiki at work, and have an interactive map and you can see who's building what today.

But when it comes to game features -- the more time you spend on paper, the more incorrect assumptions you're making, and it's just going to pile up on you.
In a sense I agree with what they are doing here, but only in a sense. I think part of the fundamental problem of FF14 is they didn't go through enough iterations early enough, or if they did, they weren't willing to give up the unfavorable ideas for the iterative process to work well.

However Bethseda's lack of planning also hurts their designs as well.

Now if I wanted to sum up my estimation of what when wrong it would be this, they say if it ain't broke don't fix it and if it is broke it's not worth fixing, well I think SE might have tried to reinvent the wheel (which isn't broken) while trying to fix broken ideas that needed replacing.

Example, they got rid of a tried and true AH and put in a broken market wards system. Then they had to fix the system. They still probably need to fix it a few times again.