system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why is a wet cloth more effective at removing stubborn dirt than a dry cloth?
gpt
Water is a really good solvent.  It can dissolve things and soften things.

With a dry cloth, you're just using friction and force alone.  The water in a wet cloth will get between the dirt particles (and also the fabric you're scrubbing) and loosen the bonds the dirt has with the surface you're cleaning.