Bad UX can be caused by confusing customer flows, failed usability or accessibility, not following relevant psychology principles, or undiscoverable features. Some examples of bad UX include Google Data Studio's onboarding tutorial, Orange's in-app messaging, USPS confusing form, Popupsmart's blocking modal, and Booking's date picker. To improve UX, avoid information overload, non-personalized UX, and non-structured self-serve support. Use friction logging, behavioral analytics, and user feedback to detect bad UX, and provide relevant product tours, tooltips at key points, and self-serve support to eliminate it.