Obviously, besides “knowing the language” (however abstract and arbitrary that may be) we all have our smaller, shorter-term goals. What are yours?
My top goal ATM is understanding the language in and of itself, as opposed to a translated version of the languages I know. For example, getting to understand そして as そして and not as the Japanese version of “and”, seeing as there are always tiny, nuanced differences to grasp.
I just want to watch Anime with the subtitles off.
Same TBH.
As an added bonus, I’ll be able to travel to Japan and converse with people.
So I can shout loud, battle-scene monologues in the shower, with confidence.
And you know, actually converse in Japanese, that’d be helpful
I’m most excited for understanding music lyrics, playing VNs and other games, and watching anime subtitleless.
So I guess those are my goals. 
I really want to be able to listen to anime songs and understand the words behind the emotion the artist is singing through. There are a few that I now understand the song is about wanting to protect someone or having feelings for someone but they can’t tell them because someone else is involved. A few that I can now understand more of, are hero related and how they don’t feel worthy or they are now worthy… If you think about it, almost like American country music… except their love, dog and truck doesn’t leave them… or not that I have been able to understand yet.
I want to play switch games in Japanese. I’m even holding off on buying one until I get a high enough level to read.
And also to make friends!
To always enjoy my time and know I am always improving my ability to be alive AND happy.
The thing that excites me the most is simply to take a long term challenge that will make me learn a lot about the Japanese culture along the way 
But as a short-term goal, reading a manga is clearly pushing me forward !
I want to be able to read light novels and listen to songs in Japanese and actually know what’s trying to be conveyed
Eventually, I just want to walk into a shop or e.g. a bar and just talk to people without having to think a lot about the language itself, just enjoy the flow of the conversation, no matter where it leads.
Since it will take me a while to get there and I’m not interested in anime or manga, the second best thing is the JLPT. I somehow got it into my head that I want to pass all of the exams and the thought of reaching N1 one day is exciting. That is a bit lame but that is what it is. 
Thirdly, being at a level where I can read books that I find really interesting and just focus on the content and not on the language would be exciting. I would mostly be reading books that would available in English anyway but read them in Japanese for the sake of practicing Japanese. But finally getting back into reading interesting content, intended for boring adults, no images, no simplified language would be great.
For example, I saw a book about Nietzsche (with some German text on the cover, which is what had caught my eye) in a tiny convenience store in Okinawa and I just ended up buying it because I thought it was fun. I might be able to somehow fight my way through it on a Kindle but since it is the printed version looking up every word I don’t know would take me forever so I believe it will be at least 2 years before I can attempt reading it. But the thought of being able to read my little Ishigaki konbini book about Nietzsche is exciting. The day will come!
Having recently rediscovered a passion for reading, I have to say that my primary goal in learning the language is having an unfettered ability to read Japanese webnovels (and light novels). There have been so many times where I’ve found a story that might interest me, only to find that:
There’s a wide world of literature that’s ripe for the reading that I would like access to, and that drives me forward.
A part of me wants to try my hand at the whole translating business to see how difficult it is, but that is far in the future.
These kind of goals are the best ones because they seem more “real,” and you’re more likely to work hard to reach them. I’m sure that you’ll be able to reach them eventually
Read books and articles without having to look things up often.
Being able to read stuff and watch anime is first stop.
Second stop is to fit into and function in daily life while doing my masters in japan.
Obviously the more exciting of my two goals here, and who knows, i might just decide to stay afterwards
My goal is to get to that moment when I see something in Japanese and be like “Aha! Now I can understand that!”. I am working for that blessed moment when I realise all the work pays off and everything works well in the brain regarding Japanese. As it happened with English, when I realised I was able to read books in English and actually understand. I am working for that pride moment!
There is also late translation. When i saw my favourite light novels have 5-10 volumes that aren’t translated, i decided to start learning Japanese.
You are aware that Japanese texts are also written without consideration as to how English speakers will read it, right? Like, the “without naming who is talking” bit is kinda inherent to Japanese prose style.
What I would love to do is read books and play games in japanese, specially the obscure stuff that’s unlikely to ever be translated. And even with the already translated stuff there is always a compromise, so being able to understand the nuance of the language is a very big motivation for me.
My short time objective goal is to pass the JLPT N4 this december!
For me, this is about living with the Japanese people and fully integrating my life with theirs. To read, write and speak their language cant be avoided if I want a trouble free life in their society. I cant be all Japanese since I’m Caucasian but I can learn the language at least.