Till what age should you take your Life Cover ?

From some last some days I am getting queries that some Life Insurance Policies are not giving cover for more than 65 yrs of age or for Tenure of more than 25 or 30 yrs and why they dont want to take those policies because they want a cover till 70 or 80 yrs of age . So People are confused on which one to take. They generally want a cover which covers them till 70-80 yrs of age or sometimes whole life