references/theories/penetration-growth.md

# Penetration Growth

## Theory

Use this as an applied decision model, not as proof that the model is correct in every market.

## Use when

- Growth requires more category buyers rather than only deeper loyalty.

## Mechanism

Increase reach, mental availability, physical availability, and buyer base.

## Applied marketing use

Challenge plans centered entirely on heavy users.

## Failure modes

- Ignoring profitable niches or distribution limits.

## Counterweights

- `smallest-viable-audience`

## Sources

- `source:sharp-how-brands-grow`