Lack of separation of power is primarily a feature of a military government.
In a typical democratic framework, like a presidential system or a cabinet system, power is usually divided among different branches: the executive, the legislative, and the judiciary. This division is known as the separation of powers. It ensures that no single entity has absolute control, and it balances the powers among various branches of government.
On the other hand, a military government usually centralizes power within a single authority or group, often led by military leaders. In such systems, the military might control the executive power and possibly influence or directly control legislative and judicial functions. This centralized control eliminates the typical checks and balances provided by a separation of powers, leading to a system where one group or leader may wield broad, unchecked authority.