Uncertainty adds its own cost
People can often tolerate a wait better when they understand what is happening. An unclear starting point, an unexplained delay or a hidden exception adds effort on top of time. The service journey needs to explain where to wait, what happens next and who can help when the normal route does not apply.
A display is not the service
A screen with a waiting message helps only when its information matches the work. A precise-looking estimate that cannot be supported may create more frustration than an honest explanation. Design the information around what the service can know and update, rather than what looks reassuring in a mock-up.
Separate without abandoning
Exceptions can slow a normal queue, but moving them elsewhere is not a solution if the next route is unclear. The customer needs a visible handover and an expectation about the review. Accessibility, language and privacy can change the right route. One line is not always one experience.
Review the whole wait
The official queue may be only part of the effort. Customers can spend time finding the start, gathering information or returning after a failed handover. A review should include those steps before declaring a wait solved. The useful measure is the task completed with understandable effort, not simply the time beside a counter.