When you fly with the same person for several hours, you can get used to each other to the point of complacency.
Your CFI might let you get away with a slip, like forgetting to use a checklist during the preflight inspection, which can lead to a normalization of deviance. Or you might be paired up with an instructor who is building their hours and following the syllabus by “checking the boxes” but not really teaching. Or maybe something got lost in translation or technique as it was taught, and the learner is ill-equipped for solo flight.
