Not an employer, but my read is this: When I'm in the office, I have little, off the cuff conversations I can't have online, where I can express and develop a

Not an employer, but my read is this: When I'm in the office, I have little, off the cuff conversations I can't have online, where I can express and develop a thought that would otherwise be gone as quickly as it came to me. IRL, I have thousands of opportunities during the day to get 10 seconds of feedback, online I'm not likely to get a response because of the context switching overhead. I don't want to be 100% in the office, but the one day a week we have at the moment is definitely positive for the whole team. Tl;dr: the creativity that can be achieved by having people to bounce ideas off is multiplied when they're in the same room.