Why a view needs to be refresh in SQL Server?
===

I have created 8-9 views in my database but there is a 1 view that I need to refresh after every couple of days. 

I searched SO db and got the question as  http://stackoverflow.com/questions/1272829/why-do-sql-server-views-needs-to-be-refreshed-every-once-in-a-while but I'm still not clear as to why that 1 view needs to be refresh and remaining 7-8 views don't require the same?

**Update:**

a. My underlying table that is being referred in the view is not change.

b. Neither the indexes hasn't changed.