What causes a pc to take forever to do something for no apparent reason?

[Brando]

I was running dydndolod for skyrim se (modding stuff) and when it came time to put the output (several gb) into a zip file it took forever despite the entire pc being at almost a resting state. I'm not sure why the computer didn't ramp up activity and go as fast as it could. Weird.

 

[Brando]

Nevermind I figured it out. Had to add texgen64.exe and dyndolod64.exe process exceptions to windows defender.