A customer called me one day, after we had some rainy weather, telling me that their dog had come inside and jumped straight onto the sofa bringing muddy paws with him. He laid down on a single cushion, pictured above, before she was able to get him off and clean.
Initial instinct would be to try to wash this immediately, which is not actually advisable in this situation. Other than the area where the dog laid down pressing the mud into the fibers, the mud was gently resting on the surface of the sofa. Attempting to wash the sofa in any way typically available to a homeowner would only allow the soil to migrate deeper into the fabric.
Once dry, this mud becomes dirt, the majority of which can be easily vacuumed away as shown in the picture above; the lower half has been vacuumed, and the upper half has not. The only area of the sofa that required wet cleaning of any kind was the center of the cushion pictured, even though the majority of the sofa was covered in mud after the original incident.
The world of soil removal is like anything else, a lot more complex than most think. Some soiling and spills are best left alone to dry, as in the above example, while some spills need to be treated immediately or they are guaranteed to require color restoration or structural repairs, other spills can simply be scooped up and wiped with a damp cloth.