Investors are known for investing not in products or companies, but people. At least the good ones. Because markets change. Products change. The only consistency you have in a startup are the founders. You invest into them assuming that they can adopt to change.
A job is the same. Yes, you ought to take an interest in what you build, be passionate about it, but you and I both know that it might change on a dime. In the end what counts are the people you work with. Are they smart? Are you learning from them? Do you feel your contributions are appreciated? Is your manager giving you enough new challenges that stretch you and enough guidance to make sure you succeed? Are you buying into the company culture?
As obvious as this is, I had to learn this lesson several times. Of course, I do want to work on something that matters as much as the next guy, but I have come to realize that if you find the right people to work with, whatever you build together will be something that matters. You will make it matter. Not only because you are motivated and dedicated, but so is everyone else.
So, for all those job seekers in the tech industry (and outside), focus on learning as much about the team as possible. Great people build great products. Set out to find a team that matches your interest and has an engineering culture you like. Obviously, do keep an eye on whether the projects you'd be working on pique your interest. And for those of you hiring, you need to remember that you cannot compromise on quality in your team, no matter how desperate you are. Because every hire will affect all future hires.
Again, these are obvious lessons, but they are also too easily forgotten.