What determines the readability?
According to an international survey*, where the Norwegian Ministry of Education and Research was involved, one in three adult Norwegians has difficulty in reading Norwegian.
This is far more than first generation immigrants and dyslexics by a long way. Nothing indicate that the situation is better in the UK, Australia, Canada and the US, rather the opposite.**
All players, who depend on a market, must take this reality into account. Several factors play a role in making a text easy to read.
Why is this so?
The working memory can recall seven plus/minus two elements of information from 12 to 30 seconds. Words with seven letters are considered long and hard to read. If the text consists of too many long words and sentences and poor variation in subsequent periods, the text becomes bureaucratic and unreadable. Every time a recipient must repeat a word or a sentence to get the meaning, you may lose him.
* Source: Adult Literacy and Life Skill Survey (ALL). ** Source: A survey (PIAAC) for 24 countries, included the US and the US, was published in October 2013.