Let me preface this by saying that I have watched all of the Netflix Marvel shows and found numerous flaws in all of them. However, I still liked Jessica Jones and Season 1 of Daredevil to a decent extent. I really disliked Luke Cage and Season 2 of Daredevil. I have no words for Iron Fist; it was that bad.

Obviously, I did not have high expectations going in. But, in a similar fashion to Jessica Jones and Daredevil, I at least expected to be entertained, even if the plot doesn't make much sense. Moreover, the showrunners were writers on Daredevil. So I had some hope before watching the show.

And boy, does this show disappoint. Every scene in so cliched and predictable. The dialogues are lifeless. As pointed out in another comment, many conversations are about how they can't let the police help them and they need to stop The Hand alone. The show drags and drags and yet, nothing happens. The plot is so stupid and boring and predictable and riddled with cliches. For all the buildup about the teaming up of the Defenders, [spoiler] they all don't get together until halfway through the series. [/spoiler]

Superhero shows need a great villain if we want to root for the hero. Season 1 of Daredevil had an amazing villain in Wilson Fisk. Jessica Jones had it with Kilgrave. I very much disliked The Hand as a villain in Season 2 of Daredevil, so it was not encouraging to see them be the villain again in The Defenders. And here, we are led to believe that Sigourney Weaver's Alexandra is a strong, all-encompassing villain. Even though Sigourney Weaver is a great actress, the character isn't written well enough for her to do anything other than look cryptically at people and speak ominously. Yet, all of this is wasted, because [spoiler] they kill her off (just like they did, stupidly, with Cottonmouth in Luke Cage) in episode 6 and now Elektra becomes the big bad villain. I never liked Elektra as a character, so making her the real villain and creating some cliched romantic/tragic tension between her and Daredevil was quite irksome. [/spoiler]

In conclusion, this show convinced me to never watch anything ever again from the Netflix Marvel universe. Eh, who am I kidding? I'll probably watch the Punisher series when it premiers at the end of this year. And I'll probably regret watching it as well, considering their track record till now.