Finding product market fit for a startup can be like using a torch to explore a dark cave. Just like you never know the size of a cave beforehand, you never know the size of a market or how much potential there is for a product or service until you start to explore it.

The torch represents the startup's product or service, which helps to shed light on the needs and pain points of potential customers. As the startup experiments and iterates on its product or service, it can use customer feedback to guide the direction of the torch, illuminating different areas of the market and helping to find the right path towards product market fit.

Just like a torch can help a cave explorer navigate through a dark cave, a well-designed product or service can help a startup navigate the challenging landscape of the market and find success, even if the market is larger or smaller than initially anticipated.