Adults want to know something before learning a topic and that can be described in a one-word question: Why? Adults have to know why they are learning a subject or they won’t want to. The benefits of learning need to be clearly shown to adult students. The training should meet the needs of the audience. An adult learner will not simply be content to learn a subject “just because”, or simply so they know it just to know it.
This contrasts with learning done by children. Kids typically don’t ask why, they will just learn something because someone told them they have to. Children are also eager learners; they find all sorts of things fascinating and will get into all sorts of activities without stopping to ask why they are learning it.
In summary, adults learn differently than children do and one of those differences is wanting to know why they are learning something. Lesson plans should include reasons for learning.