The probability that you will not understand the following contribution is high. Unfortunately, this assumption is well-founded. Very concrete experiences in teacher education as well as in adult education make us despair. pdf 
It seems to be firmly anchored in the subjective theories of teachers that at the beginning of a learning process as little as possible must be anticipated in order not to counteract the curiosity motivation, the surprise effect and the elementary need of all learners to want to "work out" any content themselves with a high willingness to exert effort.
This is why the world of teachers swears by a motivational phase at the start, based on the unquestioned assumption that motivation is the most significant factor in the learning process.
According to the current state of research, this is wrong. In the ranking of important factors influencing the learning process, motivation is far behind, just undercut by learning strategies.
Metacognition, i.e. those particularly valuable forms of self-directed planning, monitoring and evaluation of learning processes, which in some cases even correlate negatively with learning success (cf. the postdoctoral thesis by Klaus Konrad 2004), brings up the rear.
Motivation has an average correlation with learning success of r = .30, which corresponds to a common variance of less than 10% (cf. for example the meta-analyses by Köller & Baumert 2002, p. 777ff.).
Intelligence plays a dazzling role. At the beginning of dealing with a topic it is important because it helps to decode information. The correlations are r = .50, which corresponds to a common variance of about 25% with the learner's success.
The further the learning process progresses, the more subject-specific knowledge takes the place of intelligence.