Thanks for your reply. Maybe you already had interest in reading from the onset but some people do like my friends. Under genres we have fiction and non-fiction so it's not only about reading books for fun. Because some people find it difficult reading a serious book for long period, reading another genre of book that is different from the one you reading that is less serious and more fun helps keep your interest up and also helps you retain information on the informative book you are reading.
It's just like studying in school. Though I like studying, but some days I don't really get into it so what I do is maybe look at a picture book to get myself to study and it works for me. It's just like feeling tired sometimes to also work out but when you do some warm-up, you get into working out. Different people have different things that work for them.