Why do Indians break coconuts when praying to god?

Reason

Hindu mythology differentiates individual people into three categories.

1. First is a person who is bossy, adamant, cold hearted and does not care about other people. The outer hard shell of the coconut signfies this.
2. Second is a person who is very timid and scared about everything. The hairy part of the coconut signifies this.
3. Third is a person who works for community and the greater good rather than being an introvert. His heart is as white as the inner sweet part of the coconut.

By breaking a coconut in front of god, an individual pledges to god and reminds himself that he will be neither like the outer hard shell nor the hairy part of a coconut. Rather he would try to live life like the sweet white of a coconut.