<p class="ingestion featured-caption">There are a few things customers should avoid doing at high-end restaurants.Wengen Ling/Getty Images</p><ul class="summary-list"><li>Business Insider asked an <a target="_blank" class href="https://www.businessinsider.com/things-you-should-never-do-on-plane-etiquette-coach-tips-2024-8">etiquette expert</a> what people should avoid doing at high-end restaurants.</li><li>She said diners should never disregard the wait staff or arrive late to their reservation.</li></ul><p>Going out to a <a target="_blank" class href="https://www.businessinsider.com/red-flags-how-to-spot-good-steak-house-from-owners">high-end restaurant</a> can be a luxurious experience. But for patrons who are used to more <a target="_blank" class href="https://www.businessinsider.com/trying-applebees-first-time-review-photos-2023-2">casual-dining experiences</a>, eating at a fancy restaurant can be stressful.</p><p>To learn more about everything from how to dress to how to address the waitstaff, Business Insider asked <a target="_blank" href="https://www.elaineswann.com/">Elaine Swann</a>, a lifestyle and etiquette expert, to identify four <a target="_blank" class href="https://www.businessinsider.com/common-beginner-pilates-mistakes-from-longtime-instructor-2024-8">common mistakes</a> diners should avoid making at high-end restaurants. Here's what she said.</p>