You don’t know better than your client, even if you feel or consider you do. You client knows their business as they go to bed and wake up with it every day. You don’t have to go there and act like you know better and your client has to listen. You have to listen.
Listen to your client! To their management, to their employees, to all levels that are concerned with the project you are working on. Too many times you see a project that has a poor implementation because the people who are going to actually work with the new processes, or the system, or will have the new roles and responsibilities were never consulted. Implementation fails because you did not listen.
Innovation comes from everywhere, so many times the people who are actually doing the job can tell you exactly what goes wrong.
So don’t forget to listen, leave the talking and presenting for when you know what you’re dealing with and you think you have a very good solution for your client.