Software inspections are a critical aspect of developing high quality software. As model-based development methodologies gain traction, the need for model inspections has become increasingly apparent to ensure the correctness of these model-based artifacts. In the real world, ad hoc inspections are frequently carried out, often involving new and relatively inexperienced team members who are called upon spontaneously to review a particular artifact. The involvement of novices, such as trainees or student assistants, offers the advantage of shorter review cycles at a lower cost. The quality of these ad hoc inspections is generally believed to depend on various factors, many of which are related to the reviewer. Furthermore, a common belief is that longer review times indicate a more serious approach to the task, and that more time spent reviewing will lead to the identification of more defects. However, in this paper, we present the results of an experiment focused on ad hoc model inspections, challenging these assumptions. Our findings reveal that, contrary to expectations and empirical evidence from inspections of textual documents, the amount of time a reviewer chooses to spend on an ad hoc model inspection does not have a significant impact on its effectiveness. This suggests that factors other than time allocation may play a more critical role in determining the success of these inspections.