Why does all users don't see Blog option under Delve Profile ?

In our organisation one of our entities have raised question stating all the users are not able to see the Blog option under the Delve profile in office 365. 

I know the to get it enabled I can go to either of the below URL's and  users personal profile site collection will get created under "/portals/hub/personal/username"

https://contoso.sharepoint.com/portals/hub/_layouts/15/pointpublishing.aspx
https://tennantname.sharepoint.com/portals/hub/AppPages/PointPublishing.aspx

But question is why it shows Blog option for some users and why not for some users ?