Short Answer 
The answer to the riddle is a bathtub, which retains and loses water due to its built-in drainage system, eliminating the need for manual emptying. This aligns with the riddle’s clues, as bathtubs do not stay full for long periods and automatically drain after use.
Identify the Object
The answer to the riddle is a bathtub. Understanding the object described is crucial for solving the riddle. The clues guide us to realize that it naturally retains and loses water, thereby making it the likely answer.
Analyze the Clues
Look at the context clues in the riddle which indicate that nobody “empties” the object directly. Instead, it suggests a mechanism or system that allows contents to drain out. In this case, bathtubs have a built-in drainage system that means they don’t require manual emptying.
Confirm the Characteristics
Further confirming that a bathtub fits the description, consider the following points:
- It drains after use without being actively emptied.
- It does not remain full for long periods.
- It is filled, used, and then drained, aligning perfectly with the riddle’s context.