9 Things I Came to Realize at Age Thirty

1. Speak Less, Listen More

If something you want to share with a friend takes more than a minute to say, consider writing it down or recording it instead. I’ve found that I rarely meet people who are good listeners. Most people can give the right kind of “mm-hm” at the moment, but they may not even remember what was said 30 seconds ago.

Part of it is that spoken words easily lose information; part of it is that many people simply do not want to listen to you. That’s something I’ve realized in a few recent conversations. A friend’s new game, life updates, the name of their pet—we end up repeating the same topics at gatherings.

This also has to do with how important you are to the other person, and it may also just be that they don’t want to invest energy in you.

Another point, and probably an even more important one, is that after turning thirty you’re no longer young. Your words and behavior can easily turn you into a preachy old-timer. If you talk too much, young people will find it hard to interrupt you, but honestly they’re probably not interested in your deeds or stories at all. To put it in Japanese: 「身の程わきまえろ」(know your place).

If the occasion is counseling or asking for advice, that’s a different matter. But at this stage, the highest-value move is to hold back your mouth. If you have something to say, write it down, or record it as a video or a Podcast.

2. Don’t Try to Change People

I remember this very clearly: a few years ago, there was a coworker on the team whose way of doing things was drastically different (details omitted), which made working together quite painful.

I couldn’t tolerate someone slacking off and slowing down the team’s progress. I tried many things, including pointing out mistakes more proactively in Code Review, giving reminders about details in Slack, and asking questions about Pull Requests that were delayed without response—but it just didn’t work.

What I learned from that experience was that I’m not good at lecturing people or changing them, and I’m also not the kind of person who easily gets along with everyone, so whenever I wanted team members to do certain things, my tone often came across as a bit aggressive.

At the time, my former manager said to me in all seriousness: don’t try to change people; assume that people cannot change. Instead, understand the other person’s culture and try to help them. He also told me that this kind of behavior doesn’t actually help team output.

Looking back now, my manager’s words were absolutely right, but unfortunately I didn’t understand them then.

People only change when they want to change. If someone doesn’t meet requirements or expectations, either fill the gap through systems and processes, or let team culture influence them gradually. Blame is the worst possible approach.

3. Aim Lower

Whether for yourself or for others, the way to increase output is to lower expectations. If you don’t expect much from others, you won’t run into expectation gaps. For yourself, don’t exhaust yourself because of overly high standards.

4. Start with the End in Mind

Before buying something, never look only at the price tag. You also need to consider maintenance costs and ownership costs.

For example, in Japan cars are cheap to buy and can be paid in installments, but once you buy one, what comes at you is vehicle tax, acquisition tax, gas expenses, regular inspections, maintenance, and worrying about accidental scratches.

On the other hand, buy things that are easy to resell, such as Fender electric guitars

4. “No Money” and “No Time” Are Lies

What we often casually call “no money” or “no time” is fundamentally a question of priority.

When we say we don’t have time to exercise or to learn a new technology, what we really mean is: “these things are not important enough yet.”

Likewise, “no money” often really means: “the marginal benefit of this expense isn’t enough to make me reallocate my budget.”

5. Everything Is a Trade-Off

Every problem is a trade-off problem; it just depends on what matters most to you at the moment. When you need to deliver a product quickly, you inevitably sacrifice quality, and vice versa.

The same is true in life: where you live, the kind of life you lead, and the level of consumption you choose are all trade-offs.

6. 夏蟲不可語冰

Don’t argue with people whose level of understanding is too far apart from yours.

In most cases, the other person doesn’t want to have a real conversation or change their position; they just want to win until you get annoyed and embarrassed. I’m using the word “debate” here. If it’s just chatting and listening to someone’s story, then the attitude is completely different. Being able to hear voices from a different environment is a rare and valuable thing, but don’t try to change the other person with logic.

The clearest example is educational background: middle school, high school, university—the differences shown by which school someone attended are quite obvious. Of course there are always exceptions, but nine times out of ten, it’s probably about right.

Can this be changed through life experience after entering society? Of course, but it depends on luck. The lower the educational background, the more likely it reflects a poor family economy or a complicated environment, and the harder it is to escape that situation.

This happens very often on social platforms. For example, when discussing the security of Cookies, does the other person have enough knowledge? Do they understand how CSRF works? Do they know how SameSite is used? If both sides don’t understand each other at the same level, discussing Cookie security becomes meaningless.

It’s the same with the Coinhive incident I wrote about before: if the other person doesn’t understand how the code works, all they can do is instinctively answer “guilty.”

The Detention was also a tragedy caused by a gap in understanding, and even a tragedy in many Chinese families. Parents hoping their sons become dragons and their daughters become phoenixes, children carrying heavy expectations from a young age; the father who was obsessed with the慈孤觀音, and Du Meixin who deeply loved her father. To put it according to the second point, this is something outsiders can hardly change.

7. Luck Matters a Lot

I come from an IT-related background, and coding and working with new technology are ordinary parts of life. I was very lucky to catch the wave during the SaaS boom, which gave me not only a better working environment but also a relatively higher salary than in other industries.

And I had already moved to Japan before the pandemic and found a stable job. After COVID hit, remote work became the norm. During the pandemic era, jobs were hard to find, and after the pandemic, rapid AI development made it even harder for entry-level software engineers to find work.

If I had not entered the field earlier, maybe I would be worrying about the same things—worrying about how to find a job, worrying about how to accumulate experience. I think that’s luck.

8. Let Go of Ego and Focus on Results

Especially in the IT industry, people often treat making mistakes, asking others for advice, and seeking help as something shameful. When someone else proposes a better solution, some even become aggressive and irrationally question that person’s proposal.

I think a big reason for this is ego—fear that someone else will take your credit or authority. So when others perform better, this mindset arises almost instinctively.

Thirty is considered an age with substantial workplace experience. At this stage, what matters more is influence. That’s also the biggest shift I’ve realized compared with when I was younger. Help others, don’t be stingy about giving credit away, and focus on how to achieve the goal. Life becomes much easier that way.

9. Stay Positive

I don’t know if you’ve ever experienced this: talking to some people, the content itself isn’t really anything special, but somehow it just drains your energy. There are also people who, as soon as you talk to them, make you feel like you gain energy.

These people may not necessarily have bad intentions, but their communication style often carries invisible pressure that makes others feel exhausted. There are probably some signs you can infer from:

• Self-centered: They don’t listen. For them, conversation is not an exchange, but waiting for their turn to speak.
• Complaining: Repeatedly complaining about the same problems, yet not intending to take action to change
• Hidden lecturing: Even in casual conversation, they want to show superiority. Correcting your details, denying your feelings
• Good at finding problems, but only at stopping at the problem

People who bring positive energy usually have some traits too:

• Listening**:** Not just hearing, but making you feel understood.
• Emotional safety: You can openly share failure or vulnerability without worrying about being lectured
• Inspiring questions: They won’t rush to give advice, but will help you clarify your thoughts through questions
• Not only finding problems, but also willing to get their hands dirty to solve them