At a local manufacturing company, one of their packing lines had a history of customer complaints regarding missing components. Customers were threatening to drop them while return and sorting costs keep growing. This company tried audits, 100% inspection, intensive training, incentives and even disciplinary action yet components still ended up missing from the boxes.
After a series of problem solving sessions along with some experimentation, they added a simple visual work aid that solved the problem. By placing digital pictures of the components with quantities on a large, laminated sheet of paper, they constructed a standard template for each packaged assembly. Using a tray with the template, operators on the assembly line placed components on top of the corresponding picture in the quantities specified. The last operator in line visually checked the tray for completeness than placed the components in the box.
This simple solution only added a slight amount of double handling to the process and eliminated the more expensive audits, inspections, returns and sorting activities.
Watching this work aid in action, several opportunities quickly came to mind where I could implement the same concept. Try it out, modifying it to fit your application, and see if it makes an improvement.