Advantages of self publishing:

• Don't have to chase publishers/agents.
• The book makes it to the market faster because you are the sole decision maker.
• Complete Control over your book.
• Ability to publish on niche, specialized topics which publishers of mass market books may not be interested in.
• Easy to publish for friends/family.

Disadvantages of self publishing:

• Operational and financial burden of Self Publishing (Pothi.com platform eases a lot of this).
• Marketing and promotion is your responsibility.
• Since no third party has vouched for the quality of your content, reviewers and critics can ignore the book.