I work as software engineer in a small software company that has roughly 20 employees. Recently my co-worker was absent for some days so I had the idea to switch to his workplace. This is because he has a dual monitor setup while I have to work with one monitor. His workplace is a bare minimalistic setup: two monitors, a keyboard and mouse - that's it. No personal stuff like photos, no nothing.
So to increase my productivity I switched to his place for the days he was not there.
Just recently I received an SMS from him that says that it's HIS and HIS ALONE workplace and that I am ABSOLUTELY NOT allowed to use it. This raises the question to me if my behaviour was a bit rude. I sent him my excuses but still don't see how this is such a big deal to him. It's just a workspace, his computer was not even there. I just used the monitors and his chair.
So is it an absolute no-go to switch workspaces temporarily if someone is absent?