Theoretical Background: Previous studies indicate that students' learning motivation varies across learning situations and is influenced by situational characteristics such as teaching behaviour. We focus on instructional clarity as one factor that may influence expectancies and task values. Aims and Research Questions: This study combines a previously published dataset of university students' experience sampling method (ESM) self-reports about their current motivation with unpublished video recorded data of the same learning situations. We examined how lecturers' instructional clarity predicted states of students' learning motivation. Sample(s): One hundred and fifty-five preservice teachers assessed their situated expectancies and task values three times within each weekly 90-minute lecture over the period of 10 weeks. Simultaneously, video recordings of the lecturer were made and coded qualitatively for instructional clarity. Methods: We then combined students' motivation to lecturers' instructional clarity in the same learning situations. We used cross-classified multilevel models to examine the associations of ESM surveys of students' motivation (level 1; n = 2227), nested in students (level 2a; n = 155), to ratings of lecturers' instructional clarity from videos (level 2b; n = 81). Results: Our findings indicated that none of the three indicators of instructional clarity (detail of explanation, variation of explanation and logical inconsistency) predicted global measures of motivation at the learning situation level. When exploring further into the facets of motivation, a detailed explanation predicted expectations of success and effort costs. Relevance: Overall, the idea of combining objective observation and subjective assessments emerged as valuable for adequately mapping complex dynamics in teaching--learning situations.