This approach is simplistic. People can usually direct their anger and frustration, to some extent. Most of the time, there's little reason to be angry at a coworker. Even if they mess up, it's usually not a huge deal, it's relatively easy to mitigate or undo; if you need mediation, there's a manager "nearby" in the org chart to escalate to, and so on. In addition, you probably have some camaraderie from past projects and assignments etc, which provides a basis of resilience when they (or you) screw up. Staying relatively pleasant and positive is not a huge challenge.

Conversely, when upper management fucks up, and refuses to take responsibility (for example: admit to making the wrong decision, or even reverse the decision), that's when cynicism runs rampant among the rank and file. And gee, what a surprise, VPs and CEOs try to avoid underlings that speak up about the screw-ups of the brass.

So a lot of companies try to avoid a lot of people? How does that work out?

In my experience most companies work with a wide distribution of people. This "we avoid hiring people who have defects" reads as disconnected from reality. Nobody is perfect, and most companies are average and have average people.

> are you able to tolerate the less than perfect aspect of a job while still being pleasant to coworkers.

I honestly tend to get much better along with cynic people (and find them much more pleasant). In other words: tastes differ.