The idiom "rookie mistake" refers to a mistake made by someone who is new to a particular task or activity. It is often used to describe a mistake that could have been easily avoided if the person had more experience or knowledge.
For example, if a new employee at a restaurant accidentally spills a tray of drinks on a customer, it could be considered a "rookie mistake" because it is something that could have been avoided with more experience handling trays.
The term "rookie" is often used in sports to describe a new player on a team, so the idiom "rookie mistake" is also commonly used in sports to describe a mistake made by a new player who is still learning the game.
Overall, the phrase "rookie mistake" is used to describe a mistake made by someone who is inexperienced or new to a particular task or activity.
• She made a rookie mistake by not double-checking the address before sending the package.
• It was a rookie mistake for the experienced lawyer to forget to file the necessary paperwork.
• He made a rookie mistake by forgetting to bring his passport to the airport.
• The seasoned investor's rookie mistake of not diversifying his portfolio caused him a big loss.
• Making a rookie mistake by not saving the important file cost him his job.
• I made a rookie mistake and forgot to turn off the lights before leaving the house.