To be frank, BG Bosse captured leadership completely when he stated that it's basically anyone who has followers. To caveat that, there are good leaders...and there are bad leaders. No matter how it's diced up, they are still both leaders.
How one defines a good leader will depend on what is most important to them. Most should agree that a component of good leadership is the ability to accomplish the mission. I personally find this extremely important as too many times I see leadership distracted with great ideas, such as developing followers, but at the expense of completing the mission. At one time, I would have placed good leadership focused around followers...but as I get old, I'm reminded how important it is to not get side-tracked on the main purpose for taking up that leadership in the first place. As a best practice, servant-leadership works, but leadership in and of itself is purposefully founded on achieving a specific goal through a vison.
Seriously though, I'd encourage soldiers at my stage of the game to start developing the capacity to eat crow gracefully. Learn that it's okay to ask for help instead of trying to power through everything like I tried to do -- I usually complete the mission, but it was a lot more of a headache than it should have been. Ask questions. Own your mistakes, LEARN from them, instead of trying to be every other "hooah hooah ra-ra" meathead in uniform these days. Get to know your soldiers; I can't stress this enough, and it infuriates me to no end to see commanders and section leaders that have no idea what their own soldiers are like, especially since it's a simple as inviting them over to sit down with you at lunch.
Just a little story:
I had some growing up to do after AIT, but my biggest problem was asking for help. At that point in my life, I would have rather taken a fail than accept help from anyone else. When I found myself unemployed and nearing homelessness several months after AIT, I failed an APFT. Thankfully, I was in what I still consider to be the best unit in the MIRC at the time, and nearly immediately, the battalion commander, company commander, first sergeant, platoon sergeant, and my new squad leader, a SGT M, started asking me what was going on. At that time, I was couch-surfing over at different friend's houses and rationing $.25 packs of ramen. At 6'3, I weighed in at about 145 lbs.
My 1SG and I had a long talk, and he eventually got me enough guts to ask my dad to move back home, which happened. SGT M personally mentored me with getting back in shape and getting back to where I needed to be. A few months later, I got a job at Best Buy, which sucked, but hey, it paid the bills and I could actually buy my own meals for the first time in a long time. Money was still tight, so the deal was that I would drive over to SGT M's house and catch a ride up to Ft. Huachuca to use the gym up there. One day, we came back to his house to pick up my car, and his wife, another SGT in the unit, had packed about three big paper grocery bags with a lot of food in them, just for me.
I don't like admitting it, but I ugly-girl cried the entire way home. They just had their first child, SGT M was going to school, and his wife worked as an instructor on post. Where they got the money, I have no clue.
I've had to eat a lot of humble pie in my short lifetime and short career in the military. I think about it, and a lot of the heartache could have been avoided if I could have dropped whatever pride I was holding onto and just asked for help. Even on this deployment, there's a lot of instances where I think back and know that I could have made things easier for myself and others had I just the damned sense to know that I didn't have to do it all on my own. I suppose that's the core of the military: the team. How well it functions, how well those soldiers work with each other, how well they know each other... it all (hopefully!) comes together in the end.
Overall, I define Leadership as pushing people beyond their own, self-imposed limitations. However, I define Leadership differently depending on who I'm leading at that moment.
No two people respond to the same type of leadership in the same manner. Some will need you to be a hardass, a micromanager, or to just simply let them do their job. Let it be known, up front, that all people under your charge will be held accountable for their actions equally, both in recognition and in punitive measures. Communicate your goals right up front; leave no room for interpretation. To the best of your abilities, take on a "servant leader" mindset, that is to say that the strength of your leadership is reflective of how you help and support those under your charge, not the other way around. Keep your motivation internal (your personal values and goals, things that can't be taken away from you) and your focus on those under your charge. There are three metrics that you can use to measure the effectiveness of your leadership abilities.
Like - the way you make people feel.
Trust - that blind faith people have that you won't throw them under the bus.
Respect - your proven track record.
You can lead effective without the Like. It makes it easier sometimes, but shouldn't be the first thing you go for. As for trust and respect, walk in the door giving it, then you'll receive it from them.
Always keep in mind that you're just giving them what they want. If they want praise, they will do something for you to give them praise. If they want a punitive action, which may include firing them, their actions will indicate that to you as well. I've never fired someone whose actions didn't ask me to do it.
Hope that doesn't muddy up the waters. Just my .02.

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