Anyone who's played an MMO by now has got to realize that there will be expansions, and that new expansions will come with new gear that renders old "ultimate" gear obsolete or redundant. If you're VERY VERY lucky, a system may be implemented to upgrade the old gear to keep it superior (and even if they do, the system will probably be a horrible grind), but honestly you should resign yourself to the fact that while you may have Ultimate Build right now, it probably won't last.

People always complain, "I put SO MUCH WORK into weapon X, and now it's JUNK!" If they didn't see it coming, I gotta wonder what's going on in their heads... especially since folks are able to get fully decked in i90 gear after just four months of play! SE wants you playing for YEARS, and while some of that can be handled with new battles and environments, there will come a point where long-time players are asking themselves why they're going through all this stuff when the rewards are no better than what they already have. Pushing back the goalposts, giving folks new goals to strive for, is a tool for this, and if not abused can even be a good tool.