The premise of the question is that a pen is ubiquitous and used all the time by everybody. You can trust that the interviewee already understands exactly what a pen is and does (as opposed to the company's niche Foo Widget -- in this way it's similar to the classic datastructure/algorithm coding question: no, you'd never actually be solving this exact problem in the job, but it's a level playing ground to see if you can display some qualities we expect to be correlated with things you need to do in the job). If that premise fails, you (as an interviewer) need to come up with another object that does meet the criteria (say, an iPhone).
But if the interviewer is trying to have an interviewee sell them a product they up front know they're not even mildly interested in buying (as is probably the case for most of the HN crowd, we'd probably never actually buy a pen - digital for almost everything, free pens from wherever for whatever might need writing), they're either cynically hiring for a boiler room operation or doing it wrong.
That's the point of the question, isn't it. Finding an opening with the potential buyer before even working on the product. If the buyer does not care about the pen, you will try selling him how cheap, light and not leaking the pen is, so he can buy a box of ten, leave one in each of his jacket and always have a pen ready when he needs it.
In this exercise, you know nothing about the pen, so obviously it is not about the pen - you will not sell the pen if you focus on the characteristic of the pen, you need to find a need for a pen within the interviewer which is the 101 of a sales position. Like those programming questions - of course there are better way to find prime numbers or whatever you need to code - you are not here to discuss the math stuff, you are here to show you can write a few lines of code with a structure, solve a problem, ask the right question, ...
1. store info of the pen not being memorable (can use that later as per the transcript)
2. Ask for what typical activities they use a pen for. Then try and describe back to them why the pen is important based on those events. If they respond 'I don't really use a pen much'....well that might be a little harder :)
Overall an interesting transcript. I haven't studied sales much so not sure about the theory behind it all but the example seems very good. Though I'm sure there's other ways to succeed at the task without necessarily following the OP's principles exactly.
Then you make a different pitch. What counts is that you display the traits that can make you successful in sales, not that you emit a canned speech - it's not about following a script, but about improv.
Which I suck at, for the most part, and have never put much effort into getting better - and that's why I'm not in sales. But you don't need to be good at something to understand in general terms how it works.
This is a special pen, and you just carry it around with you at Walmart? I shudder to think what would happen if you were to drop it -- that happens all the time, people drop pens and stuff, and they practically never get it back! See, this is the BIC Premier. It's a nice, classy pen, it writes smoothly with no clumps or leak -- and it's $14.95 for a box of ten, so you can just have a few in your pocket, in your bag, in your glove compartment, always a nice, good pen to hand, and you can leave your anniversary pen in the place of honour on your office desk where you can use it to sign the all-important contracts that befits a pen of that stature.
