The vehicle was designed to learn the individual habits of it's driver as a safety measure. In the event the driver does something out of the ordinary (mash the pedal to the floor), there is about a second for the driver to recover so the vehicle doesn't go out of control.

It also allows the vehicle to learn more aggressive driving habits, but those are harder to be consistent with.

The reset was most likely designed so as to allow a new owner to quickly wipe the learned data or if there were two drivers sharing the car. This way the learned data does not interfere with the next driver's habits.

The reason we find it so detrimental, is that once in a while we want to 'get on it' and there is that annoying lag. Why? Because during every day traffic driving we have been conservative... easy on the gas in crowded freeways and slow braking in city traffic. The car learns the majority of your driving style... so when you 'get on it', it's outside of that normal learned data and the car believes it is not safe to let you do so right away, giving you that safety margin.

My Sprint Booster permanently removed this 'lag'. Some people don't like the Sprint Booster, but most love it.

Hope that helps. Cheers!