What's wrong with day sleep

Day sleep will makes you lazy .But a rest should be taken that's important of all .

Actually some of the most successful individuals / businessman are into the sleep pattern called Polyphasic Sleep (you should search for articles on this) which allows you to sleep 3 hours a night and take 2 quick naps during the day. In this way you will end up having a lot of extra time in your hands while you will feel well rested (note that it takes a few weeks to get used to the schedule).

My husband did night shift for few months and it adversely affected his health. He needed to change his job due to health issues.

Does nature not teach us that when we sleep at night it is better?

It is better to sleep at night. If someone sleeps in day time he or she will be very tired. And they will have health problems in time.

There is not a problem if you can do it, rest.

It's all about your lifestyle. If you are in night shift then it's favourable for you to sleep in day time. It may create a problem in family but not in office. No need to be alarmed by the article. Human body needs rest and the time can't be fixed for it.