[grey-area]

I said usually, there are sometimes one or two but the board is there to supervise and thus is outside the normal corporate structure.

[jimnotgym]

In the UK corporate governance code it is quite clear that a board should have an exec CEO and a non exec chair. The chair runs the board the CEO runs the company. The board oversees the CEO. It would be extraordinary (and pointless) not to have some execs on the board.

[grey-area]

And it would be extraordinary and pointless if the board members were all employees, it has a separate function of supervision and thus is usually mostly non-employees outside the CEOs chain of command.