Is indie publishing the same as self-publishing?

They often mean the same thing. Sometimes indie publishing refers to smaller, independent publishers who work with authors, and self-publishing refers to authors who take on the responsibilities of publishing themselves. To be very clear, someone could say they are a self-published indie author.

Do indie authors make more money than traditionally published authors?

Yes, the profit percentage is much higher for indie authors. The catch is that traditional publishing houses often have marketing departments to help sell books. But the majority of traditionally published authors never out-earn their advance and do not receive royalties.

Can a self-published book become a bestseller?

Yes. Books like Matt Dinniman's Dungeon Crawler Carl, E.L. James's Fifty Shades of Grey, Andy Weir's The Martian, and Robert Kiyosaki's Rich Dad Poor Dad were all self-published before becoming bestsellers.

Do I need a literary agent if I want to self-publish?

No. Literary agents help authors get traditionally published. If you are self-publishing, you are not looking for a publisher, so an agent is not necessary.

What is the biggest disadvantage of self-publishing?

The biggest disadvantage of self-publishing is that all of the responsibility falls on you to put out a flawless book that also hits all the hallmarks of its genre — cover design, formatting, editing, and more.