"It's hard to remember, but it's easy to do." What does this sentence mean?

It seems that the original sentence is not in this order, it should be reversed. It means that the process of thinking is difficult and must be deepened, and the result will be simple and effective; Speak with substance and act according to law. Used to describe a gentleman in ancient times, it is easy to describe the professional image of an excellent manager now. The word "Yi Tu" is used to remind the company of its social responsibility and simple and effective principles for the professionalization of managers in China.