M+ Help Arms

[simple light]

I suck, i know, but i wanna know why i suck and how i might improve a bit. For example: https://www.warcraftlogs.com/reports/q6J18WdcDvypnQmt?fight=2&type=damage-done&source=6&pins=0%24Separate%24%23244F4B%24damage%240%240.0.0.Any%24179665728.0.0.Warrior%24true%240.0.0.Any%24false%24-845
my 16

compared to:
https://www.warcraftlogs.com/reports/bW42hGpx6CtXyYHj?fight=11&type=damage-done&source=341&pins=0%24Separate%24%23244F4B%24damage%240%240.0.0.Any%24167857391.0.0.Warrior%24true%240.0.0.Any%24false%24-845

why does my cleave deal a lot less dmg ? i have a lot more casts yet do the same dmg. I just cant fathom why it hits so low

i come from raid fury (raid dead) and also still look a bit at hekili . I dont know