I was an Army officer for 5 years. Some of the officers I worked with were absolute animals- they gave it their all, worked their tails off, and dedicated themselves to the profession. Others were some of the laziest people I’ve met. Sadly the army is the same as public Ed and everyone promotes at the same rate and gets paid the same.
Teaching has the same bell curve distribution. Plenty of terrible teachers out there who don’t give it their all.