What do you like/dislike in an anime's plot?

Dislike: When the plot deviates massively half-way through the series for no apparent reason and you're left there wondering what just happened... or when a writer continuously undermines previously stated in-universe rules/laws(?) just to suit the progressing plot (I'm not really explaining the segundo point very well, but I hope you get my gist). Another peeve is when certain characters are given plot immunity (Gotei 13 of Bleach I'm looking at you).

Like: When a plot continuously keeps you on your toes and you never quite know what's coming around the corner. You're certain you know what's gonna happen seguinte and BAM, hit with a twist that no-one expected.
Of the mangá I've read (don't watch animê anymore...) I'd say Death Note is the greatest example of this.

Dislike: When the plot was clearly not thought through and the story retcons itself left and right. I hate it when its clearly focused on showing awesome fights, so it just ignores everything in between and shoves the story into a massive development with very little logic used.

I especially hate it when a character is introduced with all of this emphasis on their skill, ability, and/or infamous nature, but after that, their importance just drops like a rock. In situations where their skills would clear make a difference, or circumstances where they would should have certain knowledge or an advantage, they display no such thing and it is all left to the main character to do what they should be able to do better. Oh Medaka Box...why? Just why?

Like: A deep, interesting world where there are lots of unique characters, each with their own stories supporting their character. I want to see that, when a major development occurs, each character acts in a way completely and utterly characteristic to them, so much so, the audience has a hard time complaining. No character is present just to take up space. Every word and action is considered por the writer so that it all makes sense and links together. And, above all, they are competent enough to act according to their personality and beliefs and don't take action based on the main character taking care of everything.

Of course, I amor to see any and all interesting developments that make me pay even mais attention to what is going on. When an event that happened in the first episodes of the animê ends up having logical significance in some arc in the seguinte season, I can only smile. When an eccentric character does something surprising or impressively uncanny, I laugh. Basically, I place heavy importance on making sure plot and characters are always deeply considered at every mover and development made.

Dislike: Plot holes. I know this is pretty broad, but I absolutely hate when nonsensical things happen in a story. A character shows up someplace without any reason for being there, a character acts completely randomly considering their personality, a set of characters is kept out of a fight that's obviously important, a set of characters decides not to use their most powerful abilities for reasons unknown, an ability comes up that could have been very useful in the past, was available, and was never used... this list could go on for a while. Needless to say, I like continuity. A story has to make sense throughout, not just for a few moments here and there, and it can't just focus attention-grabbing over what's plainly the most reasonable course of action. There has to be enough realism to make the series work, and these often destroy that realism.

Like: animê plots that kill people. Sure, we all develop very strong attachments to certain characters, and I recognize that a lot of people become incredibly upset at the thought that their character may not survive into the seguinte season. However, as long as there are sacred cows, every single fight that includes them is a foregone conclusion. I like when a series dispenses with these types of characters, even going so far as to put the main character's life up for grabs and switching to a new on partway through. Perhaps this is asking too much in most series, especially since most animê spend a lot of time on their main characters and this can very easily be overdone. A character's death still has to have meaning, and too many deaths can desensitize fans. So this has to be done carefully.

Dislike: when a plot contradicts itself, or is way too predictable, like Pokemon. Also, I don't like plots that are just about boring everyday things like friendship problems. I want a bit of fantasy.

Like: twists, mysteries, adventure. When watching an anime, I like the characters to travel around a lot, so you get to see a lot of the world the animê is set in (like in ATLA, even though that's not technically an anime). I also like originality (e.g. a magical notebook (Death Note)), but I'll happily watch anything with a plot that is rather cliche, if it is well executed and the characters are interesting and likable.

Like: Emotional trauma and a beautifully executed philosophical aspect / meaning. I'm crazy about the psychological and horror genres. The series por those genres I have come across mean a lot to me. They're so much mais than "spooks" and "intense dread".

Dislike: When action in general is incorporated into the plot, or when the pacing of the plot execution gets too slow.

Dislike: Well as Exorcist and Flame have pointed out, I don't like plot holes or when a character loses his/her importance. The best example for a character losing his importance/skill, for me anyways, would be Minato from Naruto. I mean if for anyone who watches naruto it is well known that all the Hokages were hyped up for being extremely skilled ninja, but honestly can any of you say you were impressed with Minato's performance in the war at all? Another thing I dislike about a Plot is when a completely unnecessary new character is introduced. Sure I can understand that the introduction of new characters should be essential for the progression of the plot, but when a mangá author introduces a new character that is basically useless or not needed at that point in time is really annoying. This is especially bad when it is done at the end of a manga/anime. One last thing I'd say that I dislike in mangá or animê is a moment that is hyped up just to be extremely underwhelming. For instance a fight between two characters that por reputation should be incredibly powerful, but when it is actually done you end up thinking "Well this was a waste of x chapters." or something to that effect.

Like: I generally like a well thought out plot, where even years after the initial release of the anime/manga you're like "Man, was this what the author had in mind all along? He/she's a freaking genius." A great example of this is Tower of God though it is a manhwa not a manga, it still leaves you wondering how the author could be able to plan so well. Secondly I really enjoy characters that, while may not be shown often; push the plot's progression ahead smoothly and interestingly in the short times that they are shown. Well I can basically go on and on about all the things I do like, but I think I've said enough.