In my case: Always keep looking for the next opportunity; don't feel safe and indispensable or that the company is a going concern (either for you or for itself)

What business lesson did you learn the hard way?
Answers
Pick your battles with the board or the CEO carefully.
Ask your peers before going to the board with data about which you are unsure. Seriously, if only I had had Proformative a few years ago I would have been much better off at a hot startup. I went to one board member with the result of a third-party valuation (409a) which seemed a bit high to me, but he shrugged it off and thought it was fine. Well, in the board meeting where I presented the valuation I got major blowback from the other board members, and the one I went to earlier just threw me under the bus.
Had I known what the "normal" valuation range was for a company at my stage, or that valuations were really driven by the
Lesson #2: boards are unforgiving. If you do great for 6 months and then have a single slip, you may well (likely) never recover. Trust is gone that fast.
"the one I went to earlier just threw me under the bus"
That is SOP in virtually every work environment I've ever been in. Don't count on anyone to stand up for you or have your back if they sense pushback from a higher up. Even if the team is bringing proof of wrongdoing or malfeasance to light. Messengers are shot every day. Perps walk.
Contrary to what many expect, there is no team except team "me" in business environments. In the military, maybe one for all and all for one. But in real life, don't count on it. Ever!
The worst I know of is people going to
Rereading this, I know it sounds bitter. But, it really isn't. It's just reality. One that took me years to learn. I sure have seen a lot of nice folks get shafted in this way
The criticality of building a top quality team, and providing that team with feedback - both what they're doing well and where they can improve. You're only as strong as your team, so spending time building and developing your team is time well spent.
Don't discount politics. Even though our jobs are typically to help the company make the best decision(s), be careful on how you communicate your opinion and who you may embarrass in the process.
At a previous company, I exposed a problem with some branches to the Executive staff, and in the process, inadvertently threw egg on the face of my VP. Addressing the problem was the right thing to do, but in hind sight, a more tactical approach would have served me better.
As I read these comments I am drawn to Linda Wright's observations. I think I want to echo her feelings.
If I could go back, I would have worked at being a better communicator earlier. I made too many mistakes trying to be smart rather than influential.
Friendship only goes so far in business.
Based on the comments above, my reaction would be to be very selective where you go to work. Yes, everywhere has some "politics" but if you can enjoy who you work with and general level of trust, you are more likely to enjoy going to work every.
Other business lesson (learned early): focus on the big things that can make a difference. Broken processes really bother me but after getting toasted in a large business meeting by a CEO for spending time discussing less-impactful issues, never did that again. Didn't respect the CEO but learned a great lesson.
I'd agree about being selective who one works for. I've heard it often and probably said it myself. But, I don't think that is easy to do.
First, most of us need to put bread on the table so, if we need a job we need a job. Being picky often isn't an option.
And second, in my own experience, no matter who you know at a company and no matter how well you think you know the company, you'll run into unexpected bumps and warts once inside. Sometimes those bumps and warts are sufficient to make one run screaming for the door. Companies can keep all sorts of issues well hidden.
We project our best selves when we interview for jobs and try and hide our faults. Potential employers do the same.
I've taken jobs where I heard of a great, twenty year veteran boss only to find out she was a screaming mimi that threw temper tantrums - and waste baskets. No one dared let on to an outsider before they came on board.
I've taken a controller position at a company where the VP claimed to have a great
I have a good friend who once took a position with one of the nation's top banks only to be "shifted" to another position in different building with a different boss the day he reported to work.
Because I consulted and temped for many years, I was exposed to all kinds of work environments up close and personal. There are a lot of nasty environments and insane managers out there. The worst often comes out in people when the pressure is on.
And, I've had great positions where I was quite happy with the situation only to end up with a new boss who showed one face to the execs above and a complete, unrepentant jerk behind closed doors with his staff. It doesn't seem fair that such a boss could destroy a well functioning finance department where the average tenure of employees was more than eight years. But, destroy it he did. A few days after replacing 50% of the employees present when he arrived, he had the audacity to resign himself to take another position at a different company. My anger was not at him though. It was with the company owner's who allowed because they didn't look behind the wizard's curtain.
Just like finding good employees, finding good employers is a crap shoot too.
Biggest lesson learned thus far... many people in
Oh, and HR is not a "friend" to the employee -- no matter what is said, actions taken, etc, HR is strictly to protect the company (as mentioned earlier).
Sorry, is that two lessons?
Would you rather be "right" or would you rather build / maintain relationships? That is the most important lesson I've learned. The relationship has to be maintained first.
Peer support matters, and needs to be supported consistently with information so they know what you're doing. In a vacuum, they're likely to assume you're not doing anything useful (and if the CEO asks them for peer feedback, they won't have anything to offer except personal feelings). And, get to know them on a personal basis. It's that darn communication thing. I was fortunate enough to get a brutally honest 360 at my last job, which showed me my blind spots in the organization. I had great scores on my boss and subordinates, but unbelievably weird and negative feedback from peers who were operating almost strictly off rumors. My current boss has the dept heads cc: each other on our weekly CEO reports and asks us to read each others', which has made a big difference in keeping a communication cadence across the company.
Don't be overly loyal and expect similar in return.
Once I expressed my desire to transfer internally to get new challenges and was denied in a rather threatening way only to see myself 3 months later being transferred out without any influence on where to go. If I didn't accept I was as good as fired. Only good thing was the guy who threatened me to stay was fired himself.
The best advice I've learned is to make your praise public and your criticism private, across all areas. You really can't trust anyone to not repeat something negative that you say about the company in passing to the CEO or your manager, so it's just not worth it. As managers ourselves, we have a responsibility to be "on board" with company policies and procedures; our employees should never have a reason to doubt our agreement with the executive team, regardless of our true feelings. In addition, I have found that a positive attitude really is contagious within teams, so we should shut down complaints quickly and foster enthusiasm and an attitude of gratitude, starting with us.
Another:
Never call anyone an a**hole. For tomorrow, they might be your boss.
A reverse lesson - make friends, keep in touch - you never know when reputation precedes you and you get hired!
I also believe being a lifelong learner is essential. Staying on top of the latest regulatory breakthroughs, management ideas, economic trends - as well as the comings and goings deep inside the organization - are crucial to remaining relevant. Everything is becoming more complex every day, and staying on top of it all is nigh impossible; however, staying abreast of trends and developments allows you the opportunity to ask intelligent questions instead of looking like a deer in the headlights. Deers don't usually survive those encounters intact.