Disabling sleepimage unsuccessful

Over the past couple months I have repeatedly locked my sleepimage using the steps below, but after almost every reboot it's unlocked and taking up space again.

Yesterday I had a locked swapfile of 8.5 GB, and two other swapfiles of 1 GB each. Today I'm back to a normal, unlocked 8.5 GB sleepimage and one 1 GB swapfile. I'm on a desktop and don't need these space-wasters.

Disable sleep mode:

Type in the Terminal: sudo pmset -a hibernatemode 0

Remove the image:

Type in the Terminal: sudo rm /private/var/vm/sleepimage

Create a 0-byte file:

Type in the Terminal: sudo touch /private/var/vm/sleepimage

Make the file not writable:

Type in the Terminal: sudo chflags uchg /private/var/vm/sleepimage

Run these commands one by one and reboot.