Friends, A general question...

I am very new to data science. Just started practicing using R. I am a Tableau BI developer.

We can create a Linear Regression in Tableau to predict the total sales figure for the next 12 months. But we can do the same using R Studio with the help of Linear Regression algorithm. But whats the difference. Linear Regression is already available in any BI tool then why we need to go for Data Science Linear Regression.. ?

I know this is a very basic doubt but your advice will be a great help.