In English, hit is a flexible verb that we use to mean "ask," "act on," "complete," or "do." More importantly, it implies a certain level of force or the emphatic nature of the action. It can also carry a slightly negative connotation.
Uses with Emphasis
So you can go to bed, or you can "hit the bed" meaning you are so tired that you're going to basically fall into bed.
When something "hits the spot", it doesn't just fill you up. It was so good you're not only physically full, but mentally and emotionally. Something "hits the spot" when it was exactly what you wanted to eat, exactly how you wanted to eat it. Everything was basically perfect.
If you're going to "hit the books" it means you're going to sit down and study hard. It implies that you're putting forth a lot of effort to learn something.
If you "hit it off with someone" it means that you not only got along with the person, but you actually connected very well and had a good time.
If you're out to "hit the clubs," you're not just going to a club to hang out. You're going out to party hard.
And if you're going to "hit the road" or "hit the bricks" you don't just have to go, you had to leave five minutes ago. One thing is you can say to someone else "Come on, hit the road" or "Go hit the bricks" as a way of telling them to buzz off. Of the two "Hit the bricks" is a little stronger and more negative.
More Negative Connotations
If someone "hits you up for money," they're not just asking you for a few dollars, they're almost hustling you, or bugging you for money. It's the difference between "Hey, do you have a few dollars I can borrow" and "Dad, can I have some money please? please? please? please? please?"
Note: you can also "hit someone up for money," and that means you're going to ask them for money, but it still carries a sense being more emphatic in your request.
Someone who is "hitting the bottle" is not enjoying a drink, they are drinking to get drunk, and usually because they have a problem with alcohol or they're in a bad place in life. You'd never say to a friend "Let's go hit the bottle!" You'd only ever say "Man, since Jimmy's dog died he's really been hitting the bottle."
Miscellaneous
There's a few other cases, like "taking a hit," which basically means taking a piece of something, usually drugs or alcohol, but that's about it. And if something "hits you hard" it affected you strongly, either positively or negatively depending on the situation.
There are two songs that jump to mind that have nothing to do with actually beating someone: Pat Benatar's "Hit Me With Your Best Shot," and Britney Spears "Hit Me Baby One More Time." Benatar's song is saying "No matter what you try, I'm going to be alright." Spears is saying "I need you, please let me see you again."
The best way to think about hit is it's a way to a shade of meaning in English without having to use a bunch of adverbs. I hope this has helped!
Best Answer
Beethoven was working on a 10th Symphony at the time of his death. We have some of the score, but it is not done (unfinished) and therefore not complete (whole, having all its parts).
His 9th Symphony is therefore the final complete symphony -- the last symphony he completed.
I note that in novels, we can get references to "a complete first draft" if a novelist died with a novel in progress. It's unfinished, but it is complete, with all its parts. Few other art works can be found in a stage where they are complete but not finished