The Companies Act and Sport England Code of Sports Governance both require “All directors must act in the best interests of the organisation, and in a manner consistent with their legal duties”. So first of all they have a legal duty.
Any Director can be removed by the membership; at an AGM or by 100 members requiring the calling of a General Meeting as defined in Articles 12.5 and 20.5.
In addition, The President and Independent Chair are elected by members at the BMC AGM and can be removed by the members. The National Council members are elected at Area AGMs, and can be removed by Areas