While it is very flattering to us, it is not correct. Remember , if something you have written seems a bit unclear to you, it will probably seem extremely unclear to anyone else. It is worth taking a lot of effort to express yourself clearly. Of course, clarity is not all there is to good expression. The main thing we are looking for in expression is the ability to effectively communicate ideas from one mind to another.
Lecturers generally like students to stick within the word limit.
Some lecturers may even refuse to read beyond the word limit. Of course, lecturers will generally not bother to literally correct every word in an essay. They allow some leeway. So, if you are asked to submit an essay of 2,000 words, essays of between 1,800 and 2,200 words would probably be quite acceptable. But if your essay goes seriously beyond the recommended length, you run a real risk of an adverse reaction from the marker, and it is certainly not a way of ensuring higher marks.