You’re only a first-time user once
“A person is a first-time user exactly once (and in the case of the infusion pump, because of training and observation, nurses were actually never really first-time users), and in many cases a beginner for only a very short while. The first-time user scenario is always important to get right (as is that highly emotional first impression); for some products such as an airport check-in kiosk or a public emergency defibrillator, for example, it’s the most critical one and deserves the most elegant solution. But for countless other products that target people who will use the product to accomplish complex workflows over long periods of time, the first-time use case is likely only one of many secondary scenarios that deserve attention.”