Yes. If no-one complains, other people may share the same experience and things may not improve.
When we make a decision on a complaint, we may make recommendations. We expect organisations to carry these out and we check to make sure they do. These are real outcomes for the people concerned, and so our complaints investigations can lead to wider improvement across a council, health board etc and sometimes across a whole sector. You can search the reports of our investigations here, and you can find more information about how we put things right here.