Honesty is the best policy. That's what we were taught over and over again when we were kids. Always tell the truth and raise your hand if you feel like something could be done better. It sounds very nice, and I wish it could be that simple.
Needless to say, teamwork is a challenge. Everyone has a unique perspective of how things should be done, and most of the time, those perspectives don't exactly match. Especially when it comes to long-term teamwork arrangements, like a job. Very quickly, you start to remember that old childhood lesson. When teamwork isn't working smoothly, you should be honest, straightforward, and talk things out. Don't be fooled by past experiences; honesty is still the best policy. That said, it might not always come without consequences.
This particular employee seems to be quite devoted to their job. They also seem to be responsible for a little too many positions at once. Already, an unwise decision on the company's side. When a great part of your operation depends on only one person, you might get in trouble fast. Here's another saying for you: "don't put all your eggs in one basket." Pair this with a manager who fails to see the value of their employees, and you have got a perfect storm.
Dave, the manager in the story below, doesn't realise that this particular employee brings a lot to the table. Not only experience and knowledge, but also passion and dedication. Already a full package no company should pass on. That said, Dave seems a lot more interested in climbing the ladder rather than helping the team grow. It happens; not everyone has the same perspective on team effort. But, as I said, everything has consequences. The employee decided to leave (or, one could say Dave decided for them) after an "anonymous" HR initiative turned out not to be that anonymous after all. After a lot of honest conversations happened, the work relationship was broken, and both Dave and the employee parted ways. It is hard to rebuild a relationship that was fragmented by disagreement and a sense of injustice. So, when Dave tried to reach out again, things didn't go as smoothly.