4e had great potential, but much of the "oomp" of the launch was lost because their best introductory product "Keep on the Shadowfell" was priced to high to be a reasonable intro to the game. Also, at that time, Wizards was trying to pull their PR on 4e into the insider model -- meaning that it didn't have the media saturation and energy that the 3e launch had. That was strike one.
Then there was the DDI. Before the DDI, WotC representatives posting on message boards often said that the internet community, and enworld specifically, only represented a very small portion of potential customers, and the opinions given online were skewed -- kind of like the "loud majority" illusion when the most soundbyte worthy clique in a political party gets all the television coverage, no matter how connected to the rest of the group they really are.
As soon as DDI plans were announced, that position was reversed, because they wanted they dollars of online gamers. Smart move -- but THEN they proceeded to not listen to their target market again by pouring resources into the Gleemax black hole and an untested software development company (which ended in unforeseeable real human tragedy).
So, 4e is launched. KotSF is out for a version of the game which "needs" -- even more than the original version, which sprung directly out of a wargame -- miniatures. There is no miniature pack made of KotSF, just random miniature boosters, which leaves DMs to turn to third party token designers or Reaper (or even GW) minis.
The DDI doesn't really exist in any real way at launch, and the PHB contains a teasing add for it, featuring a virtual tabletop.
Fast forward to DDI's maturity, and for half the monthly cost of a WoW online account (give or take) you are offered Dragon Magazine, Dungeon Magazine, a pretty neat Character Builder and the Rules Compendium (which pretty much requires an active connection). However, .pdfs of the books for sale are ended.
DDI continues, Gleemax is dead. Even though everyone knows the VTT, Dice Roller, Character Visualizer, etc. aren't going to happen, we're still left wondering: is this all this is? DDI remains in what seems to be an alpha state for years, giving customers a nice Monster Builder tool, but not much else. The Character Builder, while still quite nice, because more and more obsolete because it doesn't regularly include or calculate all prestige class powers or bonuses or little tricky bits. More and more, things feel a bit unfinished, and the tool seems more bloated and half-assed with each update.
Lots of books come out for 4e. Lots of books can be found for sale in used bookstores or remainder outlets. It's not a failure, but it hasn't lived up to it's potential.
Then comes the 4es launch. It is basically like the 3.5 launch, except the PR is focused on making it not seem like 3.5. Meanwhile, with the huge amount of bland and seemingly randomized new powers and options that have come out prior to 4es, it seems like a good potential place to start cleaning things up a bit.
The problem?
4e never ended, so it feels like another abandoned edition -- we are in a constant state of beta to beta with no "complete" feeling product to build off of. You can use all the previous books with 4es... except, you probably weren't using those books anyway because the game was specifically designed to have so many fiddly and similar-seeming options (this power moves the enemy one square! this power pulls him one square! add in a random damage type! why is this power special and cool again?) that most people NEED a computer too to manage them.
And, in the spirit of beta to beta from a company that never completes anything for their D&D line, the nice character builder tool which could have been polished a bit more and perfected is dumped. All those blank buttons on the Adventure tools remain a potential opportunity that WotC missed. While the "new" online DDI may be advertised as an upgrade or the next step, it really is just something new. Another bit of beta software made because the previous beta software wasn't finished.
Miss potential. Who really believes that the new DDI will do everything the previous DDI did but better? And who thinks it will ever become anything resembling a "finished" suite of tools?
So, we have the DDI in a mess and the 4es books replacing the older ones on the shelf. Now we can start a new D&D group with one player who has the original 4e PHB and tries to use it without the errata. That player may not even use the CB. He probably does all his math by hand, makes his own cards, and consistently has the math wrong. They guy next to him has the PHB, and a few of the splatbooks and the old CB program still on his computer. The thirdy guy has the 4es books but doesn't have access to the new DDI so he doesn't have a CB program for his 4es characters. The fourth dude just uses everyone else's resources, and the DM has his DDI subscription still going, but he isn't even playing a character, so he isn't impressed by it.
Everyone at the table has a different FAQ or Errata, maybe even a different edition and a different tool to make their characters, and it just becomes a huge mess. What happens?
They eventually take a break from D&D -- one of those breaks that might last five years. A few of them sell their books to the used bookstore. The group picks up a system like Pathfinder or something more organic like Savage Worlds. Maybe they even go with board games instead.
Lost potential.