What was one of the most important life lessons you got out of your military time?

This is so simple. Love the soldiers. That will force me to take care of them. Walk amongst them and say thank you for their dedication, work with them, and sometimes I forced myself to suffer with them to see if we can make things better or just show my moral support to them.

I put a lot of emphasis on high morale. One time we had a field problem at Ft Riley and the temperature was zero. I was so proud of the soldiers and NCOs as the morale was high and nobody complained. I did allow them cut loose a bit at night in the dark. One young soldier danced with chem lights in the dark and we were entertained in the tent. They thought they were doing me a favor by putting me close to the heater. Man those new heaters spit out a lot of heat. I was sweating like a pig. I had a big flat rock in my office. When soldiers did something stupid-funny I put their name and date on the rock. We also had a reenactment. When the temperature is zero there exists a greater propensity for stupid things to occur like your ass getting stuck to the seat in the port-a-potty. Done on phone maybe typos.

Once upon a time, many years ago I had a very negative self image and didn't believe in myself. I joined the national guard because the active duty required a high school diploma. I reasoned that hopefully I can learn some confidence in the military. Basic helped, but still, I felt inferior and even though I tried I barely passed basic. A year later I went active duty army because I'd gotten my high school diploma, finally. Still my self image persisted and I ended up begin chaptered because I was a screw up and looking back was living a self defeating mindset. I spent 9 years as a civilian, earned associate and bachelor degrees. I'd started a family and had 3 kids. I grew up and my attitude improved a bit. 9/11 happened and I was so angry I forgot about my negative self image and resolved to see enlistment through to retirement. I learned along the way that as I served others my self worth grew. It led me to teaching and I love my life now. People at my school don't know why I give my time and talents as I do, but it is because of what I learned in the military. As I give, my value improves because I am a contributor. As I contribute it makes me feel good inside. I think I finally learned how to live out my type B personality in a way that provides personal meaning. Because of going into teaching I earned another associate degree, have only a few more classes to go on my second bachelor degree, have a master's degree, and I am in the last few stages of a doctor of education degree. All of these things are so I can do more as a contributor. I found my self worth. That is the lesson the Army taught me.

Same here. Enlisted for 4 years, no MOS guarantee. The title if Marine was all that I wanted.
I learned to prioritize, like triage. Being always squared away was number one. Time management was second. PT was third. Daily 5 mile run, gym time and swimming as time allowed. Martial arts was next. Stretching, basic exercises and Kata was next.
I should have minimized my party time, peer pressure got to me and it was back to square one.