This is the elevator panel in my hotel. Top button is '3', middle is '2' (the main floor), bottom isn't basement or '1', it's ALARM. I wonder how many times people hit the alarm to go to the main floor.
My hotel has a Sony Dream Machine. I never use a hotel alarm clock. But for some reason, the maid or prior occupant set the alarm for 0600. So at 6am, the alarm--which I did not set--started blaring. The first time I ever used this product was when it was shrieking at me, I've been pulled from a deep sleep, I don't have my glasses on yet. After figuring out what was happening (it's not a fire alarm, for example), I struggled to find something that said OFF or STOP or SHUT UP! Ultimately I unplugged it from the wall. I still don't know how to turn off the alarm.
Understanding the user persona means understanding usage. How often is the product used? Where and when? Is the persona a frequent or infrequent user? A power user or novice? This alarm clock might be perfect for a home application (as long as the owner reads the manual) but it's not appropriate for a hotel. If Sony is pushing these on hotels as a promotion, the promotion will likely fail. At least, I've learned I never want to buy one.
Buttons, door handles, credit card scanners. Design choices are everywhere. See the product from the customer's point of view and you'll often realize that what appears elegant to you is actually confusing to the user.