Twitter delivered its first boffo earnings report as a public company for the second quarter.

It crushed expectations on revenue, EPS, and most importantly, monthly active users. After doing the earnings call with analysts, we spoke with CEO Dick Costolo.

While many people were quick to say that this quarter's increase in users was all about the World Cup, Costolo emphasized that it had nothing to do with the soccer competition.

He says new users are coming to Twitter because it's improving the "onboarding" process. The most important thing for users is that they get from point of signing up for Twitter to having a lively, populated feed that "delivers value" for a new user.

The World Cup drove engagement, not usage. The engagement came from people checking out special feeds set up by Twitter. This gives Costolo confidence that Twitter can build more "experiences" around big events and big topics in the future.

Here's a lightly edited transcript of our call:

Business Insider: On the call, you said monthly active users came from product changes, not from the World Cup. Is that right? If so, what were the product changes that brought in new users?

Dick Costolo: Yeah, you are hearing that right. And it's the product changes that we've made over the course of the year that we've talked about over the course of the year that brought in those new users. So, for example, improved onboarding flows, the improved ability to get those users into experiences more quickly, and deliver immediate value. Notifications when we have content that we think is particularly relevant to those users in the form of Magic Recs, and the collection of those sorts of things are what resulted in the growth.

It was the World Cup that drove engagement among people that were already on the platform.

BI: Just to be clear, what drives a user to actually sign up for Twitter? You're a mainstream product known by almost everyone in the world. Yet, not everyone in the world uses Twitter. Some even try it and give up. So what gets people to sign up and use Twitter?

DC: When they are able to sign in, find the kinds of accounts that are interesting to them over time, and curate those accounts into a timeline that delivers value for them day in and day out. The work that we have to do is for the so many people that come to the platform and try to do that is to get them from the signup to the point where they've got a timeline that delivers value to them over and over again faster and faster.

BI: And what about users who only check once a day, or once every other day? Facebook does a good job of filtering the feed automatically; would you consider the same thing?

DC: I would say the right way to answer that is that I wouldn't rule out any kind of experiment we might be running there around algorithmically curated experiences or otherwise. The World Cup gave me confidence we can do that quite successfully now around topics and live events.

BI: Let's dig in on that, a bit. You said World Cup increased engagement, but didn't increase users. Isn't that potentially a problem? Why wouldn't that drive new users? Are you just making the people who use the product happy at the expense of new users?

DC: Let me be clear about what I am referring to. We built these very specific World Cup experiences. Those timelines that were both for each match where you could see the tweets about the match, the score of the match, the photos from the match, the accounts from the match, and then for the overall World Cup itself. Those experiences were really only accessible by people who were already logged into Twitter. And those experiences were things we prompted you to go view if you were already logged into Twitter.

We really only ran very small activation campaigns in a couple of countries to see if we could leverage those experiences as a user activation mechanism, instead of, for example, saying, "We don't know if these are going to work as an activation mechanism, but let's go do a really big thing when the World Cup starts!" We did that in a couple of countries, and those were helpful and successful, but they were very, very small, and that's how I would characterize all that.

That's all by way of saying that I think in the future, those kinds of events could be fantastic activation mechanisms for us. Those were the kinds of experiences we delivered to users around the World Cup.

BI: Can you do what you did with the World Cup for say, the NFL, or for other big events like the Oscars?

DC: That's something we've been working on for a while, and I'm very happy with where we are now there. As I mentioned on the call in my prepared remarks, I'm really excited about them, this giving me the confidence we can organize content around topics and live events like this.

BI: You brought in a new head of product, Daniel Graf. On the call, you talked about being happy with profile pages, you talked about being happy with this World Cup experience. You talked about the product roadmap that you've set and how pleased you are with it. Are Graf's hands tied? Does he have to stick to the path you've set? Or can he do what he wants to shake up the product?

DC: One of the reasons we brought Daniel in is he's very entrepreneurial. In fact, he's started his own company and ran his own company before. As I mentioned on the call, in addition to Daniel, we brought in a number of great product folks from a variety of places around the digital landscape. Within the product framework that we've laid out, those teams absolutely have the leeway and the latitude to experiment with different kinds of experiences and to innovate in ways that they may have come up with on their own. That is absolutely the case. I was just trying to paint the picture of we have a general framework for the kinds of things we want to do and as those folks have embraced that. I expect them to be entrepreneurial within that framework.

BI: The stock is going nuts, so people are happy. But, if you look at the big picture — and you probably hate this comparison — but while you added 16 million users compared with the previous quarter, Facebook added 41 million users. And Facebook has 1.3 billion users. What accounts for the huge discrepancy between the two platforms?

DC: I'll be super straight forward. We have specific goals and objectives for ourselves, and that's how we measure ourselves and think about ourselves. That's how we think about our growth, that's how we think about whether we've achieved what we want to achieve, and that's how we think about our forward-looking roadmap. It's about being a real-time information network, building the largest audience in the world and knowing that we're going to invest in being public, real-time conversational, and widely distributed. If we do those things, everything else will take care of itself. I don't think about that in the context of how it stacks up versus a company A, B, or C.

BI: Can a real-time conversational thing get to a billion monthly active users?

DC: Our goal is to have the largest audience in the world. As we said on the call, that will be comprised of monthly active users, those hundreds of millions of users who are unique visitors to our properties and don't log in, and that broader audience in syndication.

BI: Why do hundreds of millions of people come to Twitter but don't log in?

DC: I think the short answer is we provide limited experiences for them. There are really just the profile pages, and then you kind of have to know how to search for people to get value from Twitter. And yet, it's everywhere in the world. In syndication, there are so many millions of URLs leveraging our syndication tools. We make our syndication tools better and better each quarter. It's on TV more and more, it's in print more and more, so you have these tremendous amount of people being driven to the property for whom we provide limited content today.

BI: On the call, you talked about messaging as part of the product that you'd like to expand. How do you think of messaging? There's so many ways to communicate now: You can send a text, an email, a Facebook message, a Snapchat, or WhatsApp, etc. What can you do to differentiate?

DC: Specifically, being able to take a public conversation and being able to migrate it to a private channel. So, taking a public tweet, and being able to have a conversation about that public tweet with a private group of people is a compelling use case. One we see internally as something a lot of us would like to do and one that will be a real engagement driver for us.

BI: To be clear, you're saying a group of people, which is not something you can do now?

DC: I'm talking about taking a public conversation and migrating it to a private channel so that you and I can have a private channel about what the public conversation is.

BI: Facebook just carved out Facebook messages as its own standalone app. Do you see that as something you want or need to do?

DC: I think it's the case that we believe at present the best place for us to innovate is within the Twitter application because there's so much value in migrating the public conversation to the private channel.

BI: So, keep it in the app where people are comfortable and know what they're doing?

DC: That's the current plan.