Why'd they wait so long to start developing DA4?

Then it doesn't matter when they release, because they know they'd make a sale either way.  It's about new players with limited budgets and/or only one game at a time mentality. These games take people a month or more to finish.

EA has their yearly release companies. And then they have their high quality every 5 years companies. That way they can rake in money from pretty much everyone that plays video games.

The majority (like ~70% IIRC) of the DA Team is working on Anthem (at least as of Dec. that was the case), with the rest helping out on Andromeda. Pulling the DA Team to help on Andromeda wasn't the plan according to Aaryn, but they needed help so it had to be done. But according to Alexis, after MEA wrapped up the DA Team started to grow. Prior to that, they just had a small team in pre-prod. So I'm guessing at least 30% of the team is working on it now. I know they have ~15 job postings as well, so they're building a little on that as well. They might be outsourcing some work as well, maybe...

They've obviously got a lot behind Anthem, and Mike reiterated that it's the priority for BW Edmonton right now.

So yeah, it's just the situation they find themselves in. Now that the Montreal studio has merged with Motive, and Anthem has been delayed, we'll just have to wait and see what happens.

I'm not really worried about Anthem, which is still at least another year away (probably Nov. 2018), so there's plenty of breathing room between it and D2.

I don't see them putting two titles out in either the same calendar or financial year though. I think they'll want to space that revenue out some. Also, you probably don't want to potentially compete with yourself for GotY.

At any rate, it doesn't sound like DA4 is far enough along in development for a 2018 release (and I'd argue even a 2019 release), so it's largely moot...

I wouldn't be surprised if Anthem got delayed to Spring 2019. Anthem can't have the same success as MEA. Also, we don't know when DA4 actually started dev. Anthem was being worked on at the same time with MEA. I believe Anthem was supposed to be announced either at the VGA's or or next year if MEA was successful.   

I disagree with the premise of the OP. There is no evidence they sat on, delayed, tarried, dallied or waited to start DA4. I have no doubt that someone, maybe PW, was working on the outline of the narrative soon after Trespasser came out. Or perhaps after the creative team took some time off -- they did work their asses off for Trespasser.

Each franchise likely has a core team that sticks with the franchise (more or less, there are some permanent migrations). The vast majority of designers, from level designers to environmental designers -- the most labor intensive functions -- are likely shared across multiple franchises. As are likely core functions like engine and platform engineering. The rotation of designers can be inferred from the tweets of designers like @sjosz, as they hint at what projects they are working on.

The upshot being, until that army of designers is freed up to move to your franchise, velocity towards release will be lower. Not zero, but not max either. As hrungr mentioned, the army is working on Anthem right now. And if MEA had done better, MEA2 would have taken longer to release than MEA because of Anthem also. BW went from a two franchise company to three and that means all bets are off when comparing against historical release timing, unless they hire more designers.

While they are hiring for both DA and Anthem, you can't grow your army of designers by 2x or 3x overnight. Not if you want quality hires. Skilled labor is inelastic, so it's going to take more time for the same scope of work. And
I'm sure no one wants reduced scope to hit an arbitrarily earlier date.

Perhaps Bioware is making better use of resources?

Presumably MEA and Anthem writers are both working on Anthem. With more writers, maybe Anthem will have more well developed quests, and fewer fetch quests. One can hope ...

I wonder when the majority of DAI migrate toward that unnanounced game speculated to be DA4?

Why do people keep thinking that Hawke was meant to be the star of Inquisition? Cassandra might have maintained that is why they were looking for Hawke in DAI but the end of DA2 makes it quite clear that both Hawke and the Warden are missing and Leliana implies there is some sort of sinister connection between the two. Cassandra's assertion in DAI was just a rather poor attempt to cover up the lack of continuity with the end of DA2.

That is the real problem. Originally there was meant to be a DLC called Exalted March which tied off the Hawke story and to some extent the mage/Templar conflict. Then because of the poor reception for DA2, that got cancelled and as a consequence the mage/Templar conflict carried over into the beginning of Inquisition. In the interim the novel Asunder was released which shifted the responsibility for causing the conflict from Anders/Hawke to the events at the White Spire, with Fiona suddenly assuming the role of Grand Enchanter (which made no sense to me whatsoever).

There was contradictory information about Fiona's reasons for leaving the Wardens as well. In Asunder she claimed she deliberately left and returned to the Circle system with a view to causing trouble. In Inquisition she maintained she left the Wardens because they were being mean to her.

What I do feel is that Hawke's contact was originally meant to be the Hero of Ferelden, which would then have tied in with the declaration by Leliana at the end of DA2. As it was, we had the rather odd idea of the Warden suddenly heading off into the West on some wild goose chase looking for a cure for the taint, whilst it would seem that Leliana knew where they were all the time, so making a nonsense of the end of DA2. Not only that but if you romanced Leliana then at the end of Trespasser the Warden is back with her, without any indication of whether their mission was successful or not. If you romanced Morrigan then she said she was going to join him but if you romanced Alistair or Zevran then presumably their Warden is still somewhere out west.

What I would like to see in the next game is some proper tying off of various plotlines that were left hanging. The Warden searching for a cure was one, the other was the alleged trouble at Weishauppt, which seemed sinister at the end of DAI, but was largely ignored in Trespasser, with just some cryptic comment from Varric, and also entirely disproved by the events in the novel The Last Flight.

Thanks for chiming in Luke, once again I appreciate the insight!

Do we actually know when they started or just when they confirmed they were going to develop DA4?

I don't think they'd be looking for people to fill in positions like cinematic tools programmer or lead environment artist *for Dragon Age franchise*  if it was for pen and paper game or phone app...

There's already a pen and paper game, made by Green Ronin. I really like it.