We are reliably informed that all there is, is the present moment, the past has gone, committed to an uncertain memory, which will fade and decay with us. The future is not yet here and is in itself unknowable except through the medium of probability.
Seconds tick by with an increasing pressure for action ,movement and activity and once the moment has passed , it can never be reclaimed, rewound, replayed, edited or modified, all that we can do is watch to see where the ripples will spread and what other intertwined moments and actions it will collide with.
Awareness in the moment of action, easily written,incredibly hard to achieve, is, I believe the key to living without regret.