I worked as a guest of a friend from a wework in SF. Took a meeting from a phone booth and then came back to one of the desks. Later, another person went into

I worked as a guest of a friend from a wework in SF. Took a meeting from a phone booth and then came back to one of the desks. Later, another person went into the phone booth and I could hear everything. What's the purpose of the phone booth if it can isolate sound?