You're much nicer to your... new recruits than I am, you put your Wheel of Pain inside. In my jungle base I built a roof above my taskmaster, I even put a chair there so she could take a load off, but the actual wheel itself I left uncovered, no relief from the elements for the recruits. I'll eventually do something similar in my current under construction base.
I treat my thralls really well (provided they follow orders). I feed them well, I make sure they have a safe and comfortable place to live, and I provide plenty of booze and orgies. The new recruits, however, I make sure they suffer until they are broken and swear undying loyalty to me.
Meanwhile, work on the tower continues.