Analysis of a Band 5.5 essay, plus a model answer.
Most people doing IELTS have trouble getting above Band 6 in writing, in fact a large percentage of people taking IELTS around the world end up with a Band 5.5 in Writing.
There are a few reasons for this, most notably it is down to poor vocabulary and grammar. However, some students have a good level of English but do not take the time to analyse the question fully and find the issues in the question. Never write too generally about the topic, identify the issues in the task question and base your essay around those. Be very specific and keep referring back to the task question.