In spite of their manner, most drill sergeants (and drill instructors, and training instructors, etc.) don't actually hate troops.
It's all part of teaching recruits how to survive in the military. So, if they're not blacked out on hate when yelling at trainees, what are training NCOs actually thinking about?
11. The most ridiculous stuff they could make you do.
10. How bad they smell.
9. ...or how
stupid they are much work they still need.
8. Maybe they're thinking about doctrinal changes, like having to teach Coast Guardsmen the "Guardian's Creed."
7. Drill sergeants count down to the end of basic training too, but the countdowns go for years.
6. It's hard to deal with new seamen without a warm cup o' joe.
5. It's even worse for instructors' training officers.
4. They may not be angry at recruits, but they're still looking for excuses to yell. Nothing a recruit can do will save them.
3. Sometimes, the instructor is getting over a hangover. Recruits shouldn't yell their responses during this period.
2. Often, they're just tired of seeing your despair.
1. They want to break up their boredom, maybe by giving the unit impossible or confusing drill commands.