They are both films within a standalone franchise that performed better than the the previous installments in those respective franchises, while also making Marvel a ton of profit.  How is that underperforming?  The only one underperforming when it comes to superhero movies, so far, is DC.  Not a single one has went past $900M.  And their version of the Avengers, a franchise in which both installments made over $1.4B, has a shot of not even hitting $800M.

I'm confused. Why are you doubling the production budget and advertisement costs to say it breaks even there?

 That's because the studio only gets about 50% of the profits

And money from home video, streaming and merchandising?

Someone has forgotten the Dark Knight movies. The DCEU is supposed to be crap, right? So why do you expect any of the movies to pass $900M? Also, why not compare the gross of the first entries of the Marvel movies to the first entries of the DCEU movies?

The Dark Knight movies are not part of this new DCEU.  And why would I compare apples to oranges?  This is DC's Avengers movie.  Filled with some of the most known comic book characters  WW.  It should be compared to it.  Which it will probably only do half of what that movie did.  Pretty poor performance.

After this weekend, even if it only has a 56% drop (which is actually better than the DCEU average 2nd week drop of 61%), BOM is predicting it will be at $172M, or $127M away from $300M.  So, I highly doubt it will pass $300M.  BOM predicted it to have a multiplier of ~2x-2.4x its opening weekend, for a total of ~$188M-$226M.  Even if we use the more favorable MCU multiplier of 2.72x, that would still only be a final domestic take of $256M.  And if the same multiplier, and I'll include the MCU one, applies to the foreign box office, its final take home will range from $372M-$506M.  So we could see a final WW draw as low as $560M, which would be just god awful, to a best case scenario of $762M, which is still bad when comparing it the rest of the DCEU, let alone the obvious Avengers comparison, and when considering how much they need to make to break even.

DC should just adapt the DC Animated Universe, kind of like how Rocksteady adapted Batman: Animated Series for the Arkham games.

The DC Animated Universe had the perfect tone for ALL the characters, and were fun to watch. Not depressing, boring, and as lame as the DC Universe outside Wonder Woman.

Also, what blows my mind is that there is a HUGE demand for DC Universe movies.

Batman v. Superman had an $81 million opening day. Suicide Squad had a $134 million opening weekend. Wonder Woman grossed $415 million USA and $830 million worldwide.

So it's not like these movies are destined to flop. They could've blown the Avengers away (well, at least in the domestic market). Instead it's completely and intensely flopped.

It went wrong right away with Man of Steel. Just an awful tone and awful movie. As I said, they should've just adapted the DC Animated Universe. It had a great Superman tone: https://www.youtube.com/watch?v=oUcKJflBG8Q

Optimistic, action packed, but Superman isn't TOO powerful (electricity hurts him).

Also, regarding Superman, ENOUGH ZOD/LEX LUTHOR. THEY HAVE BEEN THE BAD GUY IN EVERY SINGLE MOVIE (with the exception of Superman III which uses a wanna-be Lex Luthor). There are so many Superman villains to use - Parasite, Metallo, BRAINIAC, Darkseid, Mr. Msghhsyyxxxy, Bizarro, etc. etc. ENOUGH WITH ZOD AND LEX LUTHOR. Lex is especially lame and was beyond terrible in B v. S.

This is why these movies don't reach the heights they should and why Justice League failed.

So.. i finally watched it.

It's not terrible at all. But it is just this close of actually beeing good. It's just the pacing that is horrible sometimes, wich makes it feel like bits of film that just played one after another rather than a flowing story.

That is where i think they can improve. Keep the pacing at a good level. Have the story flow in an increasing level of urgency.

When it's doing fighting and cool stuff, the movie pulls it off. It's just those awkward introduction stories having to be crammed in there cause they didn't do origin movies and some cringe worthy moments they can do without.

I must say Batman is not well portrayed either. He comes across as simply a suicidal dude with no powers in this movie. That is not what Batman is. Some of the lines betray his character aswell. Batman is supposed to always be confidant cause he always has a plan. That is not how he is portrayed in these movies and it's a disappointment.

But, they are almost there. Just need to improve a bit more.

Justice League comprises the most recognizable characters in the world and is only performing on par with a Marvel team-up of characters that most people outside of niche comic book fans had never even heard of.  The Avengers was in it's 3rd weekend before it dipped under 100 million, Justice League couldn't crack that in it's debut.  Avengers was in it's 4th weekend before being dethroned as #1 at the box office, Justice League was knocked off top in it's 2nd weekend.  Warner Bros and DC clearly and massively dropped the ball.  

DC's A-List squad (Justice League):

Marvel's A-List squad (The Avengers):

Marvel's B-List squad (Guardians of the Galaxy):

Also consider this, Sony considered these #'s such a failure for Spider-Man on his own that they cancelled their entire Spider-Man cinematic universe:

The Amazing Spider-Man (2012) 

The Amazing Spider-Man 2 (2014)

If 700-750 million for just Spider-Man by himself is a failure, how can Batman + Superman + Wonder Woman (BvS) at $873 million, & Justice League which is trending worse be considered anything but a failure?

It's not the critics, and it's not DC haters that are causing this.  Batman by himself, under the proper handling of Christopher Nolan, broke 1 billion on his own.  The DCEU hasn't been able to do that once no matter how many of their heavy hitters they throw together in the same movie (Batman, Superman, Wonder Woman, Flash, Aquaman, etc).  Majority consensus is that Warner Bros and DC rushed this universe after Man of Steel performed below their expectations, and they are being punished at the box office for it with diminished returns.