Well, I think good writing is crucial. And, it's all about communication, whether you're dealing with writing or any other means of communication. If you can't communicate, then there's no point in doing your work, because it's useless. Your audience will probably be proportional to how well you write. If you can't reach people, then you've done the work for nothing. Or, and I'm thinking in terms of scientific work, or if you're trying to write an essay for a class, for example, you may have a lot of great ideas or done a lot of work but if you can't communicate that then it's effectively useless. It's as important in the sciences as in any other discipline.