Why do many writers use a lot of description when presenting a character or a scene? Is this a writing tradition? Many characters in a book have been described in minute detail , in some ways preventing a reader from using their own imagination. The same happens with many described scenes. Is this a tradition?
I don't know why your question got voted down; it's a perfectly legitimate question. Most works I read nowadays (I don't know how we can discuss writing without discussing existing works) don't have that much description. It seems most writers nowadays adhere to the school of minimalism or follow the style of the modernists (Ezra Pound, Hemingway, etc).
If you read a lot of Hemingway's short stories, he didn't use a lot of character descriptions. In fact, he doesn't describe the characters at all in "Hills Like White Elephants." You can get away with not describing the characters. Stein said "I like to see what the characters look like and what they're wearing from the way they talk."
On the other hand if you're good with descriptions then why not use them. You have to write to your strengths. If you're bad with descriptions then don't use them; if you're bad at spelling then don't use big words. It worked with Hemingway!
I (sometimes/often) do the total opposite; I barely describe some characters and leave it almost entirely up to the reader to decide what they look like.
I may give general descriptions, such as "male", "forties", etc., but that's about it.
Why? Well, because I am writing a story and the story itself is what matters most - not what colour the protagonist's moustache is (unless, of course, the story is specifically about the colour of the protagonist's facial hair).
However, I should also point out that some characters' descriptions being highly-detailed is often vital. Take J.R.R. Tolkein's "The Hobbit" - there are a great many wonderful creatures featuring in that classic story, some little, some large, and some stunning plains upon which the action takes place, and it makes sense to describe each thoroughly due to the fantastical nature of the tale that he tells - Tolkein clearly wanted to paint a very specific picture in the reader's mind (although, I'm sure, we all now picture Martin Freeman whenever we hear the name "Bilbo Baggins" but that's the film industry for you!).
As mentioned by the user what, I too am unsure of what your "question" might be; it may well be that you yourself are unsure, but I do not condemn you (for lack of a better phrase) for your post at all as it is clear that you have some doubts and are most probably looking to ask something along the lines of "What relevance do highly-detailed character and/or scene descriptions have in a story?"
Depending on the flair of the writer's technique, the description will vary, but all writers who wish to expose the characters or scenes they are introducing and developing must use an expanse of description - not only does this picture the image in the reader's mind, it allows adaptations of the reader's imagination to rest this image in their thoughts. Heavy description also prevents an overload later on, to allow the flow of the plot; it also, in my case, provides the author with the solid image of what their character is determined to be.