PM Philosophy by Merpay’s Kawashima: Growing Through the Testing Cycle


Merpay has members with all sorts of backgrounds—and that includes product managers (PMs), the ones who lead the product. Mercan’s “Meet the Merpay PM” series features interviews between PMs to delve into why they think the way they do and what goals they’re pursuing.

In this edition, we invited Mizuno Tanno, a Merpay PM who also works to spread product management knowledge in Japan, including by interviewing PMs from various companies on his personal blog, to interview our usual interviewer, Kazuya Kawashima, on how he became a PM. Read on to find out how Kawashima’s experiences working in the SI (system integration: building systems by choosing the most appropriate hardware and software) industry, Enigmo, and Mercari UK helped him define the role of a PM!

BUYMA: The start of Kawashima’s PM career

Tanno: You joined Mercari to work on the launch of Mercari UK in 2016, and have been involved in Merpay’s launch in Tokyo since March 2018. You’re also known for actively expressing yourself as a PM. I’m really happy for the opportunity to talk with you! Are you the kind of person that’s been programming since you were little?

Kawashima: No, I’m not. My first computer was a Windows 95 my father bought back when it was really popular. The first time I really got involved with anything IT-related was when I went to college overseas and decided to minor in computer science. And the only reason I did that was because I thought “I’m on the West Coast, so I’m more likely to survive if I study computers.” (laughs) After graduating, I moved back to Japan, and started working at a company that did SI.


Merpay PM Kazuya Kawashima

Tanno: Your first career was in the SI industry? Why did you move to the web industry?

Kawashima: It was really fun to work in an industry where there was a lot of large-scale work, but to be honest, I had looked for a job without actually defining what I really wanted to do. The whole time, the thought of “I don’t belong here” kept nagging at me from the back of my mind. Then one day, someone I looked up to in my company quit. When I asked him what he was planning to do after, he said he was starting his own business. We ended up going out drinking regularly, and after a year or so, he invited me to work with him. That was Enigmo, the company behind the international online shopping site BUYMA.

Tanno: What did you do at BUYMA?

Kawashima: I was the first employee involved in product development at Enigmo—I joined the company as VP of Engineering. At the time, BUYMA had only just launched, and all the development was outsourced to an external company. My mission was to improve the systems that weren’t quite working right, move development in-house, and remake the service. It was a small venture company, so I had to do the design, development, and operation all by myself. Now that I look back at it, I guess that was the start of my career as a PM. I learned how to lead teams and projects by watching Enigmo’s president Suda and the executives.

An unexpected connection formed through a certain service

Tanno: As a PM, were you always working with BUYMA?

Kawashima: I did a lot of things. Before BUYMA really took off, we released a number of different services to build up our sales. I think that experience really helped me shape my idea of an MVP (minimum valuable product), which is used a lot in launching new businesses.

Tanno: It sounds like you had a lot of practice creating products to fit the market without overloading them with too many features. You did that for a while, then joined Mercari. What made you interested in Mercari?


Merpay PM Mizuki Tanno

Kawashima: I suppose it was when a new service I was working on failed.

Tanno: Failed?

Kawashima: As I said earlier, Enigmo went through a period of launching a number of different services. Not all of them were successful. There was one service I was in charge of that was trying to do something no one else had ever done before, so we ran into a lot of difficulties. We managed to make it through them all and planned a large-scale release, but there was a major flaw found right after it opened, and we ended up shutting it down right away.


Tanno: That must have been a shock…

Kawashima: I was pretty sad for a bit, yeah. But thanks to this service, I made an unexpected connection—I met Shintaro (Mercari CEO). The service shut down right after release, but it was talked about all throughout the internet industry. (laughs)

Tanno: That story took a surprising turn. (laughs)

Kawashima: I know, right? (laughs) When I first met Shintaro, he asked me, “You were the one who made that service? How did you do it?” The product may not have been a success, but getting it out there at all led to a new opportunity. After that, I got to know Shintaro, and when I left Enigmo to work freelance, he reached out to me and asked if I was interested in launching a UK version of Mercari. That’s when I decided to join Mercari UK.

Redefining the PM role at Mercari UK

Tanno: Back then, Mercari already had a JP version and a US version. Why were you interested specifically in launching the UK version?

Kawashima: There were two reasons. First, I was interested in working on a marketplace app. When I was at Enigmo, we actually tried making one ourselves, but it didn’t go very well. I wanted to try again, in a position where I could throw myself into development from the very beginning. The other reason was that I was drawn to the idea of trying to launch a new business overseas. I thought that I could use both the English skills I gained in college and my past career experience. We had to launch Mercari UK as a company as we launched the UK version of Mercari, and I knew it would be really difficult, but it was full of brand-new experiences for me. I’m really glad I was able to join at that time and experience launching a business overseas.

Tanno: How did you commit to the business in the two years after that?


Kawashima: I was a VP of Mercari UK, so I did all kinds of tasks, like acquiring licenses to start a new business in the UK, creating a business bank account, and more. In addition, in order to localize the service, we hired locally for PMs, engineers, etc. In order to recruit employees in the UK, you need to define the position and job description more clearly than in Japan, so we had to figure out things like what skill sets we thought people should have as a PM and the differences between junior and senior PMs. I think this gave me a great opportunity to clarify what I had always imagined as the role of a PM.

Tanno: And now you’re at Merpay.

Kawashima: Right. After Merpay was established, I had a chance to speak with Aoyagi (Merpay CEO). There, I learned that Aoyagi had experience working on overseas businesses in his previous position at GREE, and shared the same feelings of wanting to use that experience towards a new service or company. At the time, I had been working for Mercari UK for almost two years, and I thought that this could be a new opportunity for me to challenge myself as a PM.

Defining a PM as someone who runs the testing cycle and produces results

Tanno: Earlier, you said that Mercari UK was an opportunity for you to redefine what you thought of as the role of a PM. I think that the role and mission of a PM depends on the phase and standpoint of the project. What did you feel was the role of a PM in Mercari UK?

Kawashima: I think no matter what the phase, a PM to me is “someone who produces results.” People generally think of PMs as having the mission of planning and creating the product, but these days, creating the product and releasing it is pretty common. PMs need to take it one step further—make a cycle out of creating a product based on some sort of hypothesis and testing it, increase the accuracy of that cycle, and improve the PMF (product/market fit).

Tanno: So the role of a PM is to run the full testing cycle, starting with the hypothesis, and increase the accuracy to improve the PMF.

Kawashima: Exactly. For PMs, how many times they can run that testing cycle is really important. You need to set KPIs you’re happy with, prioritize, and create roadmaps. Of course, this isn’t something that can be done easily. But that’s exactly why I think that using authority and responsibility to produce results is the role of a PM. Releasing a product means asking the market why that product should exist. The feedback you receive from the market is the only shortcut to growing as a PM. The more you run that testing cycle, the faster you can grow as a PM.


Tanno: I agree that the experience you get by running the testing cycle can greatly influence the growth of a PM. As a PM reaches the senior level, do you think their role as a PM changes?

Kawashima: I think it does—in fact, I think they should consciously change it themselves. The mission of a senior-level PM is to talk about their vision of the product and to create a roadmap leading to that. Instead of the daily product management tasks, they need to understand the direction of the product as a whole and define what value to provide when. No matter how good a service is, no one can tell whether it will become a hit or not. That’s why it’s important to have a clear vision and repeat testing and implementation.

Tanno: Merpay is in its startup phase now. What do you think the future phases will be like for PMs?

Kawashima: At Merpay, the things we have to do before the launch are mostly decided already. After the release, we plan to flexibly adapt to change, rather than sticking to the structure we have now. As a PM, I’ll be running the testing cycle for the service I’m working on, talking about our clear vision, and scale the team. I think Merpay will be a good fit for anyone looking to level up their career as a PM.

Tanno: So basically, we’ll be entering a phase where the testing cycle picks up speed.

Kawashima: Yes, and I think it will get more and more interesting from here on out. I think the real strength of the Mercari Group, including Merpay, is that we move according to the company values. If we didn’t have the mission or values, teams would fall apart if the service ever went down. But because we have a shared vision and values, we have a good organization that can overcome things standing in our way. Merpay is a financial business, so it’s a little more complicated, but with the belief that people are good and everyone sharing the idea of what makes Mercari “Mercari”, and what makes Merpay “Merpay”, I hope to make the service a success.


Kazuya Kawashima

After graduating from California State University, Northridge, Kawashima worked at Information Services International-Dentsu, Ltd. before joining Enigmo Inc. in 2006. As the VP of Engineering, he worked to launch a number of new businesses, including BUYMA, and experienced Enigmo listing on TSE Mothers in July 2012. In 2014, he was appointed representative director of stulio inc. After joining Mercari in March 2016, he moved to London, where he launched the UK version of Mercari. He returned to Japan in spring of 2018, and joined Merpay as a product manager.

Mizuki Tanno

After working in research and development for robotics software at NTT Access Net Research Laboratory, Tanno worked at Virtualex Consulting and Cybozu before joining BizReach. He has been involved in product management for internet services for over ten years. In 2018, he joined Merpay as a PM. Outside of work, he works to spread product management knowledge in Japan through activities such as interviewing PMs from various companies and running events.

Related Job Postings

Product Manager, Glowth [Merpay]

Related Links Quick Reads ✨

[The Birth of Mercoin] Why is Merpay CEO Naoki Aoyagi So Fired Up? A #MercariDays Special Report!

Breaking News!! Mercari Wins Google Play Best of 2019 Grand Prize!!!! #MercariDays #BestOf2019 #GooglePlay

Looking for new adventures in Tokyo? We’re Hiring! Check out our open positions #MercariDays

Related Links In-Depth Features ✨