Who wrote the article?
This is an interesting article but reading it makes it sound like the writer is not a native English speaker; there are several grammatical and style errors in the article, some of which include:
You are not allowed to repeat answer for any question=Should be answers.
When you are better skilled, you shall get better rating=Style/Grammar issues. When you improve/have improved (you cannot be made 'skilled'). Style with 'shall', should be 'will'. Rating omits indefinite article 'a', should be 'a better rating.'
You need not only to be careful=This is more of a style issue, most times the particle/coordinator 'to' can be omitted in not only speech but formal writing in this case. It would be better rendered as=You need not only be careful.
The writer often uses the passive voice and seems a bit cautious in their writing abilities in English.