What is the origin of the idiom "hit rock bottom" and when to use it?

The origin of the idiom "hit rock bottom" is related to the idea of a miner who has dug deep into the earth and reached the very bottom layer of rock. The phrase has been in use in English since at least the mid-20th century, and it has been applied to a wide range of situations, including personal and financial struggles, addiction, and mental health issues. In general, the phrase is used to describe a situation where someone has experienced a significant and often painful setback, and where they are at the lowest point in their life, with little hope of improvement.