Chicken (and some other meat products) have a slimy, bacteria laden surface. The experts who say not to wash are mistaken. The method for washing is, however, important. My method comes from a traditional way to clean and cook chicken used in China for centuries.
Step 1. add warm water to a large bowl, add vinegar and /or salt. Place bowl in sink.
Step 2. touch chicken for the first time, removing wrapper to trash, and place chicken in bowl with as little motion and hand contact as possible, keeping one hand clean.
Step 3. turn on warm water and have soap ready; wash all surfaces of chicken by hand in bowl, then remove from bowl and wash chicken and hands under warm running water, then place on meat-only cutting board.
Step 4 rewash hands, the bowl and all surfaces of sink with soap and water.
Step 5. select pan, cut or prepare chicken and place in pan.
Step 6 rewash hands, knife, cutting board, and any other surfaces or utensils.
Step 7 cook chicken.
Seems complicated, but after a couple of times it has a logical order and is easy.