garbage in, garbage out

/ˈɡɑːr.bɪdʒ ɪn ˌɡɑːr.bɪdʒ aʊt/

phrase★Intermediate◆idiom

◆ What It Really Means

The output of a system is only as good as the input it receives.

¶ Literal Meaning

If you put garbage into a system, you will get garbage out of it.

Literal Breakdown

garbagewaste or worthless material+ininto a system or process+outthe result or output

◇ Mental Image

A system or process as a machine that processes input and produces output, where poor input leads to poor output.

◈ When to Use

A data scientist explaining why an AI model's predictions are unreliable due to poor training data.

◉ Cultural Note

The phrase became popular in the 1960s as computing systems grew more complex, emphasizing the need for clean data.

💻Technology

technical

A principle stating that the quality of output is determined by the quality of input, especially in computing and data processing.

The model's predictions were unreliable because of garbage in, garbage out.

The AI's poor performance was due to low-quality training data.

💡

Commonly used in programming, data science, and systems engineering.

Synonyms

quality in, quality outphrase

High-quality input leads to high-quality output

This phrase is widely used in software development and data science to stress the importance of data quality.

Always ensure your input data is accurate and well-structured to avoid poor outputs.

Originated in the 1960s in computer science to emphasize the importance of clean, well-structured input data.

Often used in technical fields but has broader applications in decision-making and process design.

English Dictionary