Is it necessary to separate the process of soil formation and the soil forming control factors? Why are time, topography and parent material considered as passive control factors in soil formation?

Soil formation or pedogenesis depends on weathering while soil forming factors act in union and affect the action of one another. In soil formation, it is this weathering mantle which is basic input for the soil to form and other factors play around it.

Time, topography, parent material are considered as passive control factors in soil formation because their effects are not immediately observed. They control soil development and formation.