Because IELTS is a difficult test. While most agree that IELTS is a reasonable test, it is generally regarded as one of the most challenging tests of its type.
Because IELTS has question types peculiar to it. Among the ten or so question types IELTS commonly uses, about half are used only by it or in ways unique to it. In particular, the Reading Task questions about identifying the writer's point of view is unique to IELTS and particularly challenging, since it requires
"reading between the lines," a skill that usually has to be taught.
Because IELTS uses familiar question types in unique ways. IELTS short answer questions, for example, are asked in three different ways. In all cases, at least at most testing centers, the unwritten rule is that the answers must be no longer than three words each. So, even if you have the write answer but have
expressed it in more than three words, your answer will be
counted as wrong.
Because IELTS sometimes asks even familiar question types in
deliberately tricky ways. IELTS may, for example, provide a
statement expressed in positive language as a true-or-false
question when the answer in the Listening or Reading exercise
appears in negative terms that have the same meaning as the
positive words in the question. IELTS also may ask questions
that require candidates to combine information from different
places to arrive at the correct answer. In the Listening test,
IELTS sometimes asks questions at the end of a section that
require candidates to have been keeping track throughout the
exercise; so, if the candidate has not read the question first,
he or she may not be prepared to answer.
Because IELTS has specific formats it wants followed. It's not enough merely to write or speak well, for the IELTS Writing and Speaking tasks, it is critical that candidates answer in the
ways IELTS expects them to. That means following often detailed
formats that can be learned only in IELTS Preparation courses.
In particular, there are rules about the Speaking task ? and
particular its middle section, during which candidates speak on
their own ? that are not explained to candidates in advance.
Because IELTS penalizes candidates as much as whole band point for not answering questions as asked. For example, if the Writing Task 2 question asks a candidate his or her opinion on a topic and the candidate writes about the various opinions pro and con with respect to that topic, there will be a penalty of an entire band point no matter how well the candidate writes.
There is no substitute for good, solid English skills. They are what IELTS measures. But without an in-depth introduction to the many things that are either specific to the IELTS test or the particular ways IELTS expects common tasks to be performed, it is unlikely that a candidate will earn the highest possible score.
Svend Nelson is a university lecturer and internet entrepreneur. He is director of UniRoute Limited, a Hong Kong based company with offices in Bangkok and London providing
IELTS Online Preparation and other web-based courses for university preparation. Svend lived and worked in various countries across Latin America, Europe and Asia before settling with his wife in Thailand.