Why do snails leave trails?

Producing the trail enables the snail to move across any type of ground without injuring its body. If they didn’t lubricate the surface they move along, they’d simply scrape and hurt themselves along the way.

Snails leave behind a trail of slime because it’s excreted from their bodies as they slide and move along. Snail mucus is a defence mechanism to stop any injuries being caused, as they need moisture to survive.