On the most-recent episode of The Art Of Product Podcast, Derrick Reimer and Ben Orenstein chat with Rahul Vohra, co-founder and CEO of Superhuman - the fastest email experience ever made. They talk about a great many things – and you should definitely go and listen to catch them all – but I want to focus in on one important point that they spend a bit of time talking about near the start of the podcast - the importance of picking your users.

If you want to go start trialing Superhuman right now, you can't.  They're invite-only, and may continue being invite-only for a long time.  They deliberately chose that go-to-market strategy, and consider it a strong competitive advantage:

"Most companies, especially productivity companies, make the cardinal sin of making a thing and then just throwing it over the wall and seeing what happens. And the thing is, if you do that, you get two very fundamental problems.  Number one, you don’t get to pick your users, and that has its own consequences, and number two, you can’t responsibly work on their feedback."

One of the major problems with not being able to pick your users is how it can drastically slow your growth, which he expands on:

"The ... consequence of not picking  your users is that it dampens your virality and your NPS.  Let’s say that of 10k people who join in a traditional launch, only 500 of them are the type of person that you really wanted, your upper bound for your net promoters is 500/10,000, which is really really tiny.

In addition to slowing your userbase growth, it slows your learning and product development growth:

"Now the other side of this equation, and in a sense, this is almost actually even worse, is that you cannot responsibly work on their feedback. And this is a thing that hits productivity companies particularly hard, because the surface area of what we have to build is just so huge, I mean you guys could imagine what we’ve gone through in building an email experience that’s not only as good as Gmail, but in fact better, such that people not only use it, but they love it, it’s many many many years of effort. …If you just launched a thing, threw it over the wall, and people would try it, you don’t get to fix their bugs in time. In the end, you get a reputation for being slow and not listening to users, and ultimately they end up churning out.

Imagine those 9500 people out of the 10,000 in the example above who aren't really your target market, but that you've allowed in to trial your app anyway. They're none of them likely to pay you money for any significant amount of time, but they'll all have opinions about the quality of your service.  They'll have been left wanting, and that's the story they'll tell, and they'll drown out the 500 people that really, passionately love it.  Rahul puts it really well:

"So by doing it the way we’ve done it, you both get to pick your users, and you get time to work on their feedback. And by picking your users, you get more relevant feedback, you learn faster, you increase NPS, you get more authentic genuine virality with the community that matters most to you, and by working on the feedback really fast, you get a reputation for listening really closely and also maximizing retention, and most importantly, that creates a sustainable word-of-mouth growth engine.  And if you look at the heart of any successful growth story, the core driver is always word-of-mouth.

Superhuman has done absolutely no active marketing – their total marketing spend is $0 – and yet their growth has been phenomenal. Their primary driver has been word-of-mouth: 70% or more of their new weekly customers come from word of mouth from the previous week. Picking their users has enabled them to create a word-of-mouth engine that is driving hordes of passionate traffic into their waiting arms.

This isn't the only reason to choose your users (and if you're looking for more, you can always read about why You Probably Have Too Many Free Trials), but it is the most-compelling way I've heard it expressed so far.  And this is just about eight minutes of the full episode!  Ben and Derrick put some killer questions to Rahul, who has some really well thought-out answers about engineering "delight" into your app from first principles, really important metrics that they're tracking (and what those numbers are, for those statistics junkies out there), pricing research and philosophy, and how to decide what to work on, among others.

If you're not already listening to The Art of Product, this is a great episode to jump in on. It's not their standard fare – they don't usually do interviews, and instead detail their journeys while building and launching software companies – but they always have keen insights and interesting things to learn, and this episode is no exception in that regard.