My uneducated guess is that the engineer with 10 years of experience is just very complacent. He probably can get another job even after this one, because of the 'experience', and he knows this.
But the 1st engineer is starting out so he's extra motivated. Motivation brings out creativity, energy, and result.
That doesn't really comport with what I see day-to-day. This guy definitely doesn't enjoy not being able to do anything and breaking everything that he touches; you can see that it upsets him. I don't know why HN (and people in general) are so desperate to avoid the possibility that differences in ability can exist.
IME, a lot of them boil down to the principle of least surprise and not keeping silent dependencies on things in unexpected ways. These sound trivial and obvious, but they manifest in a thousand different ways, and the habit of constantly and subconsciously checking for these things in the back of your mind while designing/coding/reading code is something that comes with practice. As I said, I don't think it's very difficult for intelligent people to learn this give a little bit of time, which is why I hire for creativity and problem-solving skills instead of direct experience with certain tools. Particularly at our current size, dead weight is infinitely costlier than it would be to a behemoth like Google. Our latest hire has never worked in anything but C and he's already more productive on our Python codebase than hire #2, who has the advantage of years of Python experience and months more tenure at this company.
> why was engineer #2 not able to adopt them?
It's not so much that engineer #2 couldn't adopt these habits: it's that he's apparently not capable of doing any actual functional implementation, which is a prerequisite for a functional implementation that's well-engineered. The point I was making was that an intelligent, creative hire missing engineering experience can easily and quickly be taught. But an experienced engineer without creativity and intelligence is not very useful.
As far as why he can't do any functional work: Every time I mention this to someone[1], people seem pretty put off, but I honestly just think he's just not a very smart guy. For some reason, the very idea of differing levels of intelligence seems to offend people, but I'm racking my brains here and I can't think of another reason why he would be so abysmally unable to do anything. In conversation with him, your response never gets addressed and he just rephrases his last point ad nauseum with no hint of comprehension. My (semi-technical) founder has pretty much been working directly with him and he hasn't had any luck in finding things for him to do either. I guess the silver lining here is that I'm batting 1000 on hiring recommendations so I hope in the future I won't be overruled on tech hiring.
[1] Not at work: that would be entirely inappropriate. I mean to friends/confidantes when they ask me how the new job is going etc.
But the 1st engineer is starting out so he's extra motivated. Motivation brings out creativity, energy, and result.