Tableau is an excellent tool for many reasons. But there are a lot of great tools for data visualization. If you ask me why Tableau is better than the others, my answer would be, the Community.

When I started using Tableau, the Tableau Community Forums helped me a lot. No questions are left unanswered, and you'll find a lot of people eager to help you. Don't hesitate to ask any questions here: https://community.tableau.com/community/forums.

The Community is all about sharing. There are many events where the Tableau Community gather to share. The Tableau User Group (TUG) is a regional event (check whether there's one near your area!) where senior users meet new users and discuss new features, tips, use cases, and more. It's also a great place to share pizzas and beers!

Don't be sad if there is no TUG near you; there are many online events, such as the Fringe Festival, organized by the Tableau Community: http://www.thefringefestival.rocks/.

Of course, there are also two major official events: the Tableau Conference in the US and the European Tableau Conference in Europe. It is the biggest Tableau event and the best place to meet people, discover all the new features to be released and cheer on your favorite competitor at the Iron Viz event.

You'll find all the events, groups, forums, links, and webinars here: https://www.tableau.com/community.

The other great way to learn is on Tableau Public.