> I've seen NPS used as a way of keeping a pulse on a community; if it drops sharply, something is clearly wrong in a way that normal monitoring can't surface.
If this is your goal (and it's a good goal), there are way better questions than NPS to use here. I'd go with a simple "How did we do today?" question, versus the convoluted NPS mechanism.
> Growth is a single number, and NPS is measuring growth, not UX.
Connect the dots for me on how NPS measures growth. Where does it tie to growth at all?
> NPS is trying to measure your customer birth rate by asking how many customers are (or intend to be) pregnant.
Horrible analogy, but ok. I'd say, if there's any equivalent, it's asking how many people think they are likely they might get pregnant ever.
> What the people who designed NPS did, I am sure (meaning I'm speculating, but giving the strongest possible interpretation), is measure some responses and compare it to the number of actual referrals, then drew the lines where the referral rates cross from negative growth to neutral grow, and from neutral growth to positive growth.
They didn't do anything like that.
> And it seems plausible that people who give a score of 6 or less won't end up referring anyone, on average.
It does seem plausible. It isn't validated by any science, but it's certainly plausible. (Like the earth is plausibly flat.)
> Since NPS is an indirect growth metric, the better answer may be to simply measure your growth directly.
Well, let's let the author try to convince you that NPS is a harmful, horrible number to summarize a company's performance on.
He would tell you that NPS is only like earnings or revenues if we allowed either to have 50% or more of their data filled with arbitrary numbers, not audited data collected from state-licensed specialists who would lose their job if it was discovered the data was manufactured whole cloth.
The author would also tell you that NPS is easily gamed and there's no checking on whether that is or not. He wrote extensively in the article the various techniques that folks can game the numbers. If this is a number reported to shareholders, shareholders should insist (No, Demand!) that the numbers be corroborated by a neutral third party that will accept liability for any errors. (No surety insurer will guarantee such a liability, for the risk of error or misrepresentation is way too high.)
As you stated, most use follow-up questions to get a richer understanding of the customer. What the author would tell you is that it's clear the NPS recommendation question taints those followup questions and diminishes their validity and inherent value. If the true goal is to learn a richer understanding of customer experience, there are many better ways to achieve it.
In other words, the author believes if executives want a simple metric that is better than NPS, a random number generator is the fastest and cheapest way to achieve it. Why bother with customers at all, if all you're going to do is squander your interaction with them on such a foolish metric.
The original draft had more detail. As did the backstory piece we wrote. Editors cut it down for page count. (It was originally a foreword to a book on web form design, which was all about the buttons and the fields.)
It wasn't simple on the back-end. Your estimate of "man-weeks" is off by an order of magnitude, because of the back-end system complexity.
As the article states, it started with the button, which, as you quite rightly point out, dominoed into a lot of changes and thinking about edge cases that didn't exist before. The point I was trying to make was that it started with the button.
The big story here isn't that adding this particular button will yield $300m in revenue. The story was that, by watching users, we saw an opportunity to reap $300m. And we took it and it worked.
The important thing here isn't that a company implemented guest checkout. It's that when they did it, because we could see the problem in our research, they found $300m in revenue. Guest checkout won't work for everyone, but doing research like this likely will.
If it's a retainer, then they pay you up front for a certain number of hours you'll be available. This can be at a higher fee than the other work.
Another alternative is to just have an on-demand hourly rate that is higher than your normal rate. You could have pre-scheduled "office hours" at the regular rate, but if they want you at other times, they get to decide to pay you a little more.
There goes the Dow Jones average.