What do most people do when they're unhappy?
They share. Share their feelings, their frustrations and their anger.
In many, if not most cases, I think they're looking for commiseration and sympathy. Misery loves company.
But is seeking commiseration from your fellow workers a wise or foolish move? The answer is Foolish!, and there are two big reasons why.
First, everything you say to anyone -- even your most trusted associate -- can and often does become political ammunition. I've seen this happen many times, and if you're politically aware, you probably have too. To notice it, look for a comment prefaced by, "Bill thinks..." or "Jane is really angry about...". The person mentioned in the statement is, at that very moment, being betrayed by the speaker. The reason may be as insignificant as for a laugh, or as weighty as to change the power alignment on an important debate. Whatever the reason for the betrayal, it couldn't have happened if the original confessor had simply kept their unhappiness to themselves.
The second reason to keep your unhappiness hidden has been made much more obvious by the corporate focus on "engaged" versus "disengaged" employees. Empirical evidence shows that "engaged" employees (whatever they might be), are much more productive than "disengaged" employees. And there are two classes of disengaged -- active and inactive. Of course, actively disengaged employees are seen as the most corrosive. So how would a manager spot an "actively disengaged" employee? They're the complainers trying to bring down their co-workers, of course. One complainer dragging others down is, however, another's confessor looking for a shoulder to cry on. And the conventional solution to having "actively disengaged" employees is to get them OUT of the company. The only way to ensure you aren't classified as "actively disengaged", is to not look "actively disengaged".
So what's an employee to do? You're stuck with that micro-manager as a boss (or whatever your personal cross is to bear), so how do you suffer through it?
If you have to talk it out -- do so only with someone not in the company, and preferably someone not connected to the company. Or better yet, tell your dog about it.
If you want to offer constructive criticism, then go beyond just complaining, and offer real alternatives, and a way to make improvements. And talk to the person who is the focus of your issue, not a pal in the office (or plant).