There are a few advantages of an electronic funds transfer (EFT), including less "float" time, meaning the time it takes for a paper check to clear the federal reserve. It is less labor intensive on the banking side, and it ensures that consumers receive funds sooner. EFT also renders mailing payments obsolete.
Eliminating float time can save consumers money in overdraft fees because the money from an EFT will be immediately available in most cases. Also, it generally won't be placed on hold as a check can be, which delays the receiving of funds. On the consumer side, it is reassuring to have access to funds immediately, and on the banking side, it is ideal to have funds confirmed and available in a timely manner.