Most likely it is because life happens. Of course when you file an extension it is not an extension to pay, just an extension to complete the return and file it.I have seen times when someone could not get their partnership papers until after the normal filing deadline, so the choice is the file an extension or do an amendment. Filing an extension is simpler and less confusing for the taxpayer as well as the IRS.There are times where some kind of disaster hits shortly before the tax deadline. In some parts of the country itu2019s floods, other parts of the country are fires and lots of things in between.There are many things that can happen to a person or family that are more important to take care of than completing the tax return by mid-April.So when done properly, it doesnu2019t save any money or postpone the payment due date, but it will delay any refund.