Spoilers for the latest Marvel flick can be found in this piece!
When you're writing a movie like Avengers: Infinity War, it's already enough of a balancing act to tell a story that contains scores of heroes interacting with each other in order to save the day. The same can be said for developing the villains in a given movie too, and this very subject has come from the various think pieces and audience comments that cited the apparent lack of developed backstory for Thanos's Black Order in Avengers: Infinity War. However, if you look at this summer's monster hit from a certain point of view, the lack of backstory makes perfect sense. Joe Russo in particular explained the lack of extensive Black Order action as a reaction to the following concern, noting,
I think people have been waiting 10 years to have the Marvel heroes together in a 2 and half hour film. So If I started to go into the history of them- that's a whole other movie altogether. Thanos is the true bad guy of the movie, you don't want the sub-villains overshadowing the super-villain.
From the standpoint of the audience who, whether they've seen Thor: Ragnarok or not, find themselves in the middle of what feels like an extension to that film's finale, it could be a bit confusing to see Ebony Maw, Proxima Midnight, and the rest of the Black Order appear out of nowhere with little to no context. So it may have felt like the hotly teased group of villains were somewhat random interlopers by time Avengers: Infinity War finally introduced them to the public at large. And yet, when you really think about the remarks above, they really don't need a huge prologue and/or introduction to fit into the story.
As Joe Russo told the audience of Iowa City High School, which was reported on by their Little Hawk Student Newspaper (via Pastebin), the focus of Avengers: Infinity War isn't the introduction of the Black Order, but moreso the fulfillment of the promise of conflict between Earth's mightiest heroes and the mad titan himself, Thanos. Ever since that first post-credits sequence that teased his desire to challenge The Avengers themselves, this inevitable match-up has been the endgame, with every step of the way leading toward Avengers: Infinity War's events. So in the grand scheme of the payoff that the film is trying to land, fleshing out something like the lackeys working in the name of Thanos actually seems kind of strange. Still, the Black Order being fairly easily bested was certainly something that was a concern to some of the fans --especially comics fans -- whilst commenting about the movie on this site.
Whether you see the Black Order as either a memorable side note or distracting excess to Avengers: Infinity War, neither of those outcomes spoil the film's plot in any way. So, if you can take or leave the children of Thanos, we're guessing you were still able to get behind the stakes of the biggest tug of war between good and evil in the MCU so far. If that's not the biggest sign that The Russo Brothers, Christopher Markus and Stephen McFeeley have done their jobs as a creative team correctly, then we don't know what is.