In my open plan office I have:

- People walking past my desk

- People walking behind me

- People walking in front of me, over the "wall"

- A team that regularly has stand up meetings behind me

- Coworkers that talk loudly at their own desks, near mine

- Coworkers that talk loudly in a small more private area, ~10ft away

- A small meeting room with a door that doesn't isolate noise very well

- A kitchen ~20ft away with a loud espresso machine

Plus, I'm in a large room and can hear conversations up to 50ft away. Given the number of people, there's nearly always one happening.

In a library, you've got a quiet space with an expectation that people will keep their voices down. Study desks often have high walls in the front and to the sides, to block out visual noise. They're also often isolated from major traffic areas.

Libraries are designed to optimize intellectual work and study, open plan offices are absolutely not.

In the company's mind, everyone in the office is there to focus on exactly the task at hand all the time. In reality, it comes in spurts and each person has those at different times. When people are in there unfocused, they just distract the people who are focused.

But I think it also helps that most of the other people in the library are probably strangers, and if a couple of them are talking it's probably about something quite different from what you're working on.

"Team" conversations that might possibly be relevant to your stuff are the worst distractions.

If you want to focus on your work and take breaks to do the rest you go to the library.

I always chose the coffee shop, so open offices don't bother me hugely. The caveat is that a good pair of headphones is a must.

This is the key thing--our brains process familiar and unknown voices differently. Recognition of a familiar entity and the ensuing reactions are automatic, and they all have a processing cost.

In the workplace, they are, unless you have an office with a door you can close.