The directions on the can tell you to brush one way. the reason for this is because there is paraffin wax in the stripper . The way it works is the wax comes to the surface to create a seal to keep the solvents from evaporating. That's why as soon as you apply it leave it alone to work on the paint.If you continue to brush it you break the seal the solvents evaporate and there is nothing left to attack the paint.The trick is to apply as much stripper as you can . Pouring it on is best and use a rag with gloves to spread as quickly as you can . Then with some help cover it with plastic and let it work.The stripper will not dissolve the plastic and keeps the solvents from evaporating . You can eat through layers of paint and thick this way .