I view this process as a dating process. Some people marry the first person they date. That is Early Decision. Others date a number of people and they marry the right person. That is Early Action or Regular Action.
Some of the saddest posts on the internet -- and frequently some of the most poorly-written, which may be a clue -- are the ones from deferred students looking for a way to improve their odds come April.
Early applicants take up as much as 25 percent of an incoming class. If you're the kind of person who buys movie tickets on-line so you can choose the best seat, you know that the later it gets, the fewer options you have.