The Beginning, The Present, And The End.

Riddle: I control what once was, what is, and what is to come. Some know not to waste me, whilst others take me for granted. What am I?

Answer: Time.

Source: https://www.riddles.com/index.php/8366

I control what once was, what is, and what is to come. Some know not to waste me, whilst others take me for granted. What am I? — The beginning, the present, and the end. by Kieran Berridge v1.

Riddle: I control what once was, what is, and what is to come. Some know not to waste me, whilst others take me for granted. What am I? Answer: Time. — by Kieran Berridge v2.